diff --git a/Cargo.lock b/Cargo.lock
index 46c3c00de13c..f01b5b365f99 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -42,7 +42,7 @@ version = "0.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e8b47f52ea9bae42228d07ec09eb676433d7c4ed1ebdf0f1d1c29ed446f1ab8"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "cipher",
  "cpufeatures",
  "opaque-debug 0.3.0",
@@ -130,15 +130,6 @@ version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a4c527152e37cf757a3f78aae5a06fbeefdb07ccc535c980a3208ee3060dd544"
 
-[[package]]
-name = "arrayvec"
-version = "0.4.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cd9fd44efafa8690358b7408d253adf110036b88f55672a933f01d616ad9b1b9"
-dependencies = [
- "nodrop",
-]
-
 [[package]]
 name = "arrayvec"
 version = "0.5.2"
@@ -273,7 +264,7 @@ checksum = "83137067e3a2a6a06d67168e49e68a0957d215410473a740cea95a2425c0b7c6"
 dependencies = [
  "async-io",
  "blocking",
- "cfg-if 1.0.0",
+ "cfg-if",
  "event-listener",
  "futures-lite",
  "libc",
@@ -386,7 +377,7 @@ checksum = "5e121dee8023ce33ab248d9ce1493df03c3b38a659b240096fcbd7048ff9c31f"
 dependencies = [
  "addr2line",
  "cc",
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "miniz_oxide",
  "object 0.27.1",
@@ -435,7 +426,7 @@ dependencies = [
 [[package]]
 name = "beefy-gadget"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "async-trait",
@@ -472,7 +463,7 @@ dependencies = [
 [[package]]
 name = "beefy-gadget-rpc"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "beefy-gadget",
  "beefy-primitives",
@@ -492,7 +483,7 @@ dependencies = [
 [[package]]
 name = "beefy-merkle-tree"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "beefy-primitives",
  "sp-api",
@@ -502,7 +493,7 @@ dependencies = [
 [[package]]
 name = "beefy-primitives"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -571,16 +562,6 @@ dependencies = [
  "digest 0.10.3",
 ]
 
-[[package]]
-name = "blake2-rfc"
-version = "0.2.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d6d530bdd2d52966a6d03b7a964add7ae1a288d25214066fd4b600f0f796400"
-dependencies = [
- "arrayvec 0.4.12",
- "constant_time_eq",
-]
-
 [[package]]
 name = "blake2b_simd"
 version = "1.0.0"
@@ -612,7 +593,7 @@ dependencies = [
  "arrayref",
  "arrayvec 0.7.2",
  "cc",
- "cfg-if 1.0.0",
+ "cfg-if",
  "constant_time_eq",
  "digest 0.10.3",
 ]
@@ -810,12 +791,6 @@ dependencies = [
  "smallvec",
 ]
 
-[[package]]
-name = "cfg-if"
-version = "0.1.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
-
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -834,7 +809,7 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c80e5460aa66fe3b91d40bcbdab953a597b60053e34d684ac6903f863b680a6"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "cipher",
  "cpufeatures",
  "zeroize",
@@ -890,11 +865,11 @@ dependencies = [
 
 [[package]]
 name = "ckb-merkle-mountain-range"
-version = "0.3.2"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f061f97d64fd1822664bdfb722f7ae5469a97b77567390f7442be5b5dc82a5b"
+checksum = "56ccb671c5921be8a84686e6212ca184cb1d7c51cadcdbfcbd1cc3f042f5dfb8"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if",
 ]
 
 [[package]]
@@ -1049,7 +1024,7 @@ version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "931ab2a3e6330a07900b8e7ca4e106cdcbb93f2b9a52df55e54ee53d8305b55d"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
 ]
 
 [[package]]
@@ -1165,7 +1140,7 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "738c290dfaea84fc1ca15ad9c168d083b05a714e1efddd8edaab678dc28d2836"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
 ]
 
 [[package]]
@@ -1174,7 +1149,7 @@ version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c02a4d71819009c192cf4872265391563fd6a84c81ff2c0f2a7026ca4c1d85c"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "crossbeam-utils",
 ]
 
@@ -1184,7 +1159,7 @@ version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6455c0ca19f0d2fbf751b908d5c55c1f5cbc65e03c4225427254b46890bdde1e"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "crossbeam-epoch",
  "crossbeam-utils",
 ]
@@ -1195,7 +1170,7 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ec02e091aa634e2c3ada4a392989e7c3116673ef0ac5b72232439094d73b7fd"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "crossbeam-utils",
  "lazy_static",
  "memoffset",
@@ -1208,7 +1183,7 @@ version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1f25d8400f4a7a5778f0e4e52384a48cbd9b5c495d110786187fc750075277a2"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "crossbeam-utils",
 ]
 
@@ -1218,7 +1193,7 @@ version = "0.8.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ff1f980957787286a554052d03c7aee98d99cc32e09f6d45f0a814133c87978"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "once_cell",
 ]
 
@@ -1497,7 +1472,7 @@ version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "339ee130d97a610ea5a5872d2bbb130fdf68884ff09d3028b81bec8a1ac23bbc"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "dirs-sys-next",
 ]
 
@@ -1679,7 +1654,7 @@ version = "0.8.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7896dc8abb250ffdda33912550faa54c88ec8b998dec0b2c55ab224921ce11df"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
 ]
 
 [[package]]
@@ -1904,7 +1879,7 @@ version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cc04871e5ae3aa2952d552dae6b291b3099723bf779a8054281c1366a54613ef"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "js-sys",
  "log",
  "serde",
@@ -1940,7 +1915,7 @@ version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e94a7bbaa59354bc20dd75b67f23e2797b4490e9d6928203fb105c79e448c86c"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "redox_syscall",
  "windows-sys 0.36.1",
@@ -1998,7 +1973,7 @@ version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e6988e897c1c9c485f43b47a529cef42fde0547f9d8d41a7062518f1d8fc53f"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "crc32fast",
  "libc",
  "libz-sys",
@@ -2038,7 +2013,7 @@ checksum = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
 [[package]]
 name = "fork-tree"
 version = "3.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
 ]
@@ -2062,7 +2037,7 @@ checksum = "85dcb89d2b10c5f6133de2efd8c11959ce9dbb46a2f7a4cab208c4eeda6ce1ab"
 [[package]]
 name = "frame-benchmarking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -2085,7 +2060,7 @@ dependencies = [
 [[package]]
 name = "frame-benchmarking-cli"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "Inflector",
  "array-bytes",
@@ -2137,7 +2112,7 @@ dependencies = [
 [[package]]
 name = "frame-election-provider-solution-type"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro-crate",
  "proc-macro2",
@@ -2148,7 +2123,7 @@ dependencies = [
 [[package]]
 name = "frame-election-provider-support"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-election-provider-solution-type",
  "frame-support",
@@ -2164,7 +2139,7 @@ dependencies = [
 [[package]]
 name = "frame-executive"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -2184,7 +2159,7 @@ version = "15.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df6bb8542ef006ef0de09a5c4420787d79823c0ed7924225822362fd2bf2ff2d"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "parity-scale-codec",
  "scale-info",
  "serde",
@@ -2193,7 +2168,7 @@ dependencies = [
 [[package]]
 name = "frame-support"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "bitflags",
  "frame-metadata",
@@ -2225,7 +2200,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "Inflector",
  "cfg-expr",
@@ -2239,7 +2214,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural-tools"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support-procedural-tools-derive",
  "proc-macro-crate",
@@ -2251,7 +2226,7 @@ dependencies = [
 [[package]]
 name = "frame-support-procedural-tools-derive"
 version = "3.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2261,7 +2236,7 @@ dependencies = [
 [[package]]
 name = "frame-support-test"
 version = "3.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-support-test-pallet",
@@ -2284,7 +2259,7 @@ dependencies = [
 [[package]]
 name = "frame-support-test-pallet"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -2295,7 +2270,7 @@ dependencies = [
 [[package]]
 name = "frame-system"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "log",
@@ -2313,7 +2288,7 @@ dependencies = [
 [[package]]
 name = "frame-system-benchmarking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -2328,7 +2303,7 @@ dependencies = [
 [[package]]
 name = "frame-system-rpc-runtime-api"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "sp-api",
@@ -2337,7 +2312,7 @@ dependencies = [
 [[package]]
 name = "frame-try-runtime"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "parity-scale-codec",
@@ -2508,7 +2483,7 @@ dependencies = [
 [[package]]
 name = "generate-bags"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "chrono",
  "frame-election-provider-support",
@@ -2555,7 +2530,7 @@ version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "js-sys",
  "libc",
  "wasi 0.9.0+wasi-snapshot-preview1",
@@ -2568,7 +2543,7 @@ version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7fcd999463524c52659517fe2cea98493cfe485d10565e7b0fb07dbba7ad2753"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "wasi 0.10.0+wasi-snapshot-preview1",
 ]
@@ -2782,7 +2757,7 @@ checksum = "848e9c511092e0daa0a35a63e8e6e475a3e8f870741448b9f6028d69b142f18e"
 dependencies = [
  "arbitrary",
  "lazy_static",
- "memmap2 0.5.0",
+ "memmap2",
  "rustc_version",
 ]
 
@@ -2805,7 +2780,7 @@ checksum = "75f43d41e26995c17e71ee126451dd3941010b0514a81a9d11f3b341debc2399"
 dependencies = [
  "bytes",
  "fnv",
- "itoa 1.0.1",
+ "itoa",
 ]
 
 [[package]]
@@ -2861,7 +2836,7 @@ dependencies = [
  "http-body",
  "httparse",
  "httpdate",
- "itoa 1.0.1",
+ "itoa",
  "pin-project-lite 0.2.7",
  "socket2",
  "tokio",
@@ -2989,7 +2964,7 @@ version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7a5bbe824c507c5da5956355e86a746d82e0e1464f65d862cc5e71da70e94b2c"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
 ]
 
 [[package]]
@@ -3048,15 +3023,9 @@ dependencies = [
 
 [[package]]
 name = "itoa"
-version = "0.4.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b71991ff56294aa922b450139ee08b3bfc70982c6b2c7562771375cf73542dd4"
-
-[[package]]
-name = "itoa"
-version = "1.0.1"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1aab8fc367588b89dcee83ab0fd66b72b50b72fa1904d7095045ace2b0c81c35"
+checksum = "4217ad341ebadf8d8e724e264f13e593e0648f5b3e94b3896a5df283be015ecc"
 
 [[package]]
 name = "jobserver"
@@ -3226,7 +3195,7 @@ version = "0.11.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72c1e0b51e7ec0a97369623508396067a486bd0cbed95a2659a4b863d28cfc8b"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "ecdsa",
  "elliptic-curve",
  "sha2 0.10.2",
@@ -3291,7 +3260,6 @@ dependencies = [
  "pallet-session-benchmarking",
  "pallet-society",
  "pallet-staking",
- "pallet-staking-reward-fn",
  "pallet-timestamp",
  "pallet-tips",
  "pallet-transaction-payment",
@@ -3445,7 +3413,7 @@ version = "0.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "afe203d669ec979b7128619bae5a63b7b42e9203c1b29146079ee05e2f604b52"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "winapi",
 ]
 
@@ -3549,7 +3517,7 @@ dependencies = [
  "libp2p-core",
  "libp2p-swarm",
  "log",
- "lru 0.8.0",
+ "lru",
  "prost",
  "prost-build",
  "prost-codec",
@@ -3918,25 +3886,16 @@ version = "0.4.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "abb12e687cfb44aa40f41fc3978ef76448f9b6038cad6aef4259d3c095a2382e"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "serde",
  "value-bag",
 ]
 
 [[package]]
 name = "lru"
-version = "0.7.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e999beba7b6e8345721bd280141ed958096a2e4abdf74f67ff4ce49b4b54e47a"
-dependencies = [
- "hashbrown",
-]
-
-[[package]]
-name = "lru"
-version = "0.8.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "936d98d2ddd79c18641c6709e7bb09981449694e402d1a0f0f657ea8d61f4a51"
+checksum = "b6e8aaa3f231bb4bd57b84b2d5dc3ae7f350265df8aa96492e0bc394a1571909"
 dependencies = [
  "hashbrown",
 ]
@@ -3952,9 +3911,9 @@ dependencies = [
 
 [[package]]
 name = "lz4"
-version = "1.23.2"
+version = "1.24.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aac20ed6991e01bf6a2e68cc73df2b389707403662a8ba89f68511fb340f724c"
+checksum = "7e9e2dd86df36ce760a60f6ff6ad526f7ba1f14ba0356f8254fb6905e6494df1"
 dependencies = [
  "libc",
  "lz4-sys",
@@ -3962,9 +3921,9 @@ dependencies = [
 
 [[package]]
 name = "lz4-sys"
-version = "1.9.2"
+version = "1.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dca79aa95d8b3226213ad454d328369853be3a1382d89532a854f4d69640acae"
+checksum = "57d27b317e207b10f69f5e75494119e391a96f48861ae870d1da6edac98ca900"
 dependencies = [
  "cc",
  "libc",
@@ -4039,15 +3998,6 @@ dependencies = [
  "rustix",
 ]
 
-[[package]]
-name = "memmap2"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "723e3ebdcdc5c023db1df315364573789f8857c11b631a2fdfad7c00f5c046b4"
-dependencies = [
- "libc",
-]
-
 [[package]]
 name = "memmap2"
 version = "0.5.0"
@@ -4083,7 +4033,7 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ce95ae042940bad7e312857b929ee3d11b8f799a80cb7b9c7ec5125516906395"
 dependencies = [
- "lru 0.8.0",
+ "lru",
 ]
 
 [[package]]
@@ -4166,7 +4116,7 @@ version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2be9a9090bc1cac2930688fa9478092a64c6a92ddc6ae0692d46b37d9cab709"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "downcast",
  "fragile",
  "lazy_static",
@@ -4181,7 +4131,7 @@ version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "86d702a0530a0141cf4ed147cf5ec7be6f2c187d4e37fcbefc39cf34116bfe8f"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "proc-macro2",
  "quote",
  "syn",
@@ -4277,7 +4227,7 @@ dependencies = [
  "matrixmultiply",
  "nalgebra-macros",
  "num-complex",
- "num-rational 0.4.0",
+ "num-rational",
  "num-traits",
  "rand 0.8.5",
  "rand_distr",
@@ -4403,7 +4353,7 @@ checksum = "9f866317acbd3a240710c63f065ffb1e4fd466259045ccb504130b7f668f35c6"
 dependencies = [
  "bitflags",
  "cc",
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "memoffset",
 ]
@@ -4415,17 +4365,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f17df307904acd05aa8e32e97bb20f2a0df1728bbc2d771ae8f9a90463441e9"
 dependencies = [
  "bitflags",
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "memoffset",
 ]
 
-[[package]]
-name = "nodrop"
-version = "0.1.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72ef4a56884ca558e5ddb05a1d1e7e1bfd9a68d9ed024c21704cc98872dae1bb"
-
 [[package]]
 name = "nohash-hasher"
 version = "0.2.0"
@@ -4458,17 +4402,6 @@ dependencies = [
  "winapi",
 ]
 
-[[package]]
-name = "num-bigint"
-version = "0.2.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "090c7f9998ee0ff65aa5b723e4009f7b217707f1fb5ea551329cc4d6231fb304"
-dependencies = [
- "autocfg",
- "num-integer",
- "num-traits",
-]
-
 [[package]]
 name = "num-bigint"
 version = "0.4.3"
@@ -4491,12 +4424,12 @@ dependencies = [
 
 [[package]]
 name = "num-format"
-version = "0.4.0"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bafe4179722c2894288ee77a9f044f02811c86af699344c498b0840c698a2465"
+checksum = "54b862ff8df690cf089058c98b183676a7ed0f974cc08b426800093227cbff3b"
 dependencies = [
- "arrayvec 0.4.12",
- "itoa 0.4.8",
+ "arrayvec 0.7.2",
+ "itoa",
 ]
 
 [[package]]
@@ -4511,24 +4444,12 @@ dependencies = [
 
 [[package]]
 name = "num-rational"
-version = "0.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c000134b5dbf44adc5cb772486d335293351644b801551abe8f75c84cfa4aef"
-dependencies = [
- "autocfg",
- "num-bigint 0.2.6",
- "num-integer",
- "num-traits",
-]
-
-[[package]]
-name = "num-rational"
-version = "0.4.0"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d41702bd167c2df5520b384281bc111a4b5efcf7fbc4c9c222c815b07e0a6a6a"
+checksum = "0638a1c9d0a3c0914158145bc76cff373a75a627e6ecbfb71cbe6f453a5a19b0"
 dependencies = [
  "autocfg",
- "num-bigint 0.4.3",
+ "num-bigint",
  "num-integer",
  "num-traits",
 ]
@@ -4599,7 +4520,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c7ae222234c30df141154f159066c5093ff73b63204dcda7121eb082fc56a95"
 dependencies = [
  "bitflags",
- "cfg-if 1.0.0",
+ "cfg-if",
  "foreign-types",
  "libc",
  "once_cell",
@@ -4690,7 +4611,7 @@ checksum = "20448fd678ec04e6ea15bbe0476874af65e98a01515d667aa49f1434dc44ebf4"
 [[package]]
 name = "pallet-assets"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4704,7 +4625,7 @@ dependencies = [
 [[package]]
 name = "pallet-authority-discovery"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -4720,7 +4641,7 @@ dependencies = [
 [[package]]
 name = "pallet-authorship"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -4735,7 +4656,7 @@ dependencies = [
 [[package]]
 name = "pallet-babe"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4759,7 +4680,7 @@ dependencies = [
 [[package]]
 name = "pallet-bags-list"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -4779,7 +4700,7 @@ dependencies = [
 [[package]]
 name = "pallet-bags-list-remote-tests"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-election-provider-support",
  "frame-support",
@@ -4798,7 +4719,7 @@ dependencies = [
 [[package]]
 name = "pallet-balances"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4813,7 +4734,7 @@ dependencies = [
 [[package]]
 name = "pallet-beefy"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "beefy-primitives",
  "frame-support",
@@ -4829,7 +4750,7 @@ dependencies = [
 [[package]]
 name = "pallet-beefy-mmr"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "beefy-merkle-tree",
@@ -4852,7 +4773,7 @@ dependencies = [
 [[package]]
 name = "pallet-bounties"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4870,7 +4791,7 @@ dependencies = [
 [[package]]
 name = "pallet-child-bounties"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4889,7 +4810,7 @@ dependencies = [
 [[package]]
 name = "pallet-collective"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4906,7 +4827,7 @@ dependencies = [
 [[package]]
 name = "pallet-conviction-voting"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "assert_matches",
  "frame-benchmarking",
@@ -4923,7 +4844,7 @@ dependencies = [
 [[package]]
 name = "pallet-democracy"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4941,7 +4862,7 @@ dependencies = [
 [[package]]
 name = "pallet-election-provider-multi-phase"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -4965,7 +4886,7 @@ dependencies = [
 [[package]]
 name = "pallet-election-provider-support-benchmarking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -4978,7 +4899,7 @@ dependencies = [
 [[package]]
 name = "pallet-elections-phragmen"
 version = "5.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -4996,7 +4917,7 @@ dependencies = [
 [[package]]
 name = "pallet-fast-unstake"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -5014,7 +4935,7 @@ dependencies = [
 [[package]]
 name = "pallet-gilt"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5029,7 +4950,7 @@ dependencies = [
 [[package]]
 name = "pallet-grandpa"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5052,7 +4973,7 @@ dependencies = [
 [[package]]
 name = "pallet-identity"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "enumflags2",
  "frame-benchmarking",
@@ -5068,7 +4989,7 @@ dependencies = [
 [[package]]
 name = "pallet-im-online"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5088,7 +5009,7 @@ dependencies = [
 [[package]]
 name = "pallet-indices"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5105,7 +5026,7 @@ dependencies = [
 [[package]]
 name = "pallet-membership"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5122,7 +5043,7 @@ dependencies = [
 [[package]]
 name = "pallet-mmr"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ckb-merkle-mountain-range",
  "frame-benchmarking",
@@ -5140,8 +5061,9 @@ dependencies = [
 [[package]]
 name = "pallet-mmr-rpc"
 version = "3.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
+ "anyhow",
  "jsonrpsee",
  "parity-scale-codec",
  "serde",
@@ -5155,7 +5077,7 @@ dependencies = [
 [[package]]
 name = "pallet-multisig"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5171,7 +5093,7 @@ dependencies = [
 [[package]]
 name = "pallet-nomination-pools"
 version = "1.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5188,7 +5110,7 @@ dependencies = [
 [[package]]
 name = "pallet-nomination-pools-benchmarking"
 version = "1.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -5208,7 +5130,7 @@ dependencies = [
 [[package]]
 name = "pallet-nomination-pools-runtime-api"
 version = "1.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "sp-api",
@@ -5218,7 +5140,7 @@ dependencies = [
 [[package]]
 name = "pallet-offences"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5235,7 +5157,7 @@ dependencies = [
 [[package]]
 name = "pallet-offences-benchmarking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -5258,7 +5180,7 @@ dependencies = [
 [[package]]
 name = "pallet-preimage"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5275,7 +5197,7 @@ dependencies = [
 [[package]]
 name = "pallet-proxy"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5290,7 +5212,7 @@ dependencies = [
 [[package]]
 name = "pallet-ranked-collective"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5308,7 +5230,7 @@ dependencies = [
 [[package]]
 name = "pallet-recovery"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5323,7 +5245,7 @@ dependencies = [
 [[package]]
 name = "pallet-referenda"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "assert_matches",
  "frame-benchmarking",
@@ -5341,7 +5263,7 @@ dependencies = [
 [[package]]
 name = "pallet-scheduler"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5357,7 +5279,7 @@ dependencies = [
 [[package]]
 name = "pallet-session"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5378,7 +5300,7 @@ dependencies = [
 [[package]]
 name = "pallet-session-benchmarking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5394,7 +5316,7 @@ dependencies = [
 [[package]]
 name = "pallet-society"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5408,7 +5330,7 @@ dependencies = [
 [[package]]
 name = "pallet-staking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-election-provider-support",
@@ -5431,7 +5353,7 @@ dependencies = [
 [[package]]
 name = "pallet-staking-reward-curve"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro-crate",
  "proc-macro2",
@@ -5442,7 +5364,7 @@ dependencies = [
 [[package]]
 name = "pallet-staking-reward-fn"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "sp-arithmetic",
@@ -5451,7 +5373,7 @@ dependencies = [
 [[package]]
 name = "pallet-sudo"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5465,7 +5387,7 @@ dependencies = [
 [[package]]
 name = "pallet-timestamp"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5483,7 +5405,7 @@ dependencies = [
 [[package]]
 name = "pallet-tips"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5502,7 +5424,7 @@ dependencies = [
 [[package]]
 name = "pallet-transaction-payment"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-support",
  "frame-system",
@@ -5518,7 +5440,7 @@ dependencies = [
 [[package]]
 name = "pallet-transaction-payment-rpc"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "jsonrpsee",
  "pallet-transaction-payment-rpc-runtime-api",
@@ -5528,23 +5450,25 @@ dependencies = [
  "sp-core",
  "sp-rpc",
  "sp-runtime",
+ "sp-weights",
 ]
 
 [[package]]
 name = "pallet-transaction-payment-rpc-runtime-api"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "pallet-transaction-payment",
  "parity-scale-codec",
  "sp-api",
  "sp-runtime",
+ "sp-weights",
 ]
 
 [[package]]
 name = "pallet-treasury"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5561,7 +5485,7 @@ dependencies = [
 [[package]]
 name = "pallet-utility"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5577,7 +5501,7 @@ dependencies = [
 [[package]]
 name = "pallet-vesting"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5592,7 +5516,7 @@ dependencies = [
 [[package]]
 name = "pallet-whitelist"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-benchmarking",
  "frame-support",
@@ -5653,19 +5577,19 @@ dependencies = [
 
 [[package]]
 name = "parity-db"
-version = "0.3.16"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2bb474d0ed0836e185cb998a6b140ed1073d1fbf27d690ecf9ede8030289382c"
+checksum = "3a7511a0bec4a336b5929999d02b560d2439c993cccf98c26481484e811adc43"
 dependencies = [
- "blake2-rfc",
+ "blake2",
  "crc32fast",
  "fs2",
  "hex",
  "libc",
  "log",
  "lz4",
- "memmap2 0.2.3",
- "parking_lot 0.11.2",
+ "memmap2",
+ "parking_lot 0.12.1",
  "rand 0.8.5",
  "snap",
 ]
@@ -5709,7 +5633,7 @@ version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0d32c34f4f5ca7f9196001c0aba5a1f9a5a12382c8944b8b0f90233282d1e8f8"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "hashbrown",
  "impl-trait-for-tuples",
  "parity-util-mem-derive",
@@ -5771,7 +5695,7 @@ version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d76e8e1493bcac0d2766c42737f34458f1c8c50c0d23bcb24ea953affb273216"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "instant",
  "libc",
  "redox_syscall",
@@ -5785,7 +5709,7 @@ version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "28141e0cc4143da2443301914478dc976a61ffdb3f043058310c70df2fed8954"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "redox_syscall",
  "smallvec",
@@ -6014,7 +5938,7 @@ dependencies = [
  "fatality",
  "futures",
  "futures-timer",
- "lru 0.8.0",
+ "lru",
  "parity-scale-codec",
  "polkadot-erasure-coding",
  "polkadot-node-network-protocol",
@@ -6044,7 +5968,7 @@ dependencies = [
  "futures",
  "futures-timer",
  "log",
- "lru 0.8.0",
+ "lru",
  "parity-scale-codec",
  "polkadot-erasure-coding",
  "polkadot-node-network-protocol",
@@ -6184,7 +6108,7 @@ dependencies = [
  "futures-timer",
  "indexmap",
  "lazy_static",
- "lru 0.8.0",
+ "lru",
  "parity-scale-codec",
  "polkadot-erasure-coding",
  "polkadot-node-network-protocol",
@@ -6304,7 +6228,7 @@ dependencies = [
  "futures-timer",
  "kvdb",
  "kvdb-memorydb",
- "lru 0.8.0",
+ "lru",
  "merlin",
  "parity-scale-codec",
  "parking_lot 0.12.1",
@@ -6408,6 +6332,7 @@ dependencies = [
  "assert_matches",
  "async-trait",
  "futures",
+ "futures-timer",
  "parity-scale-codec",
  "polkadot-node-core-pvf",
  "polkadot-node-primitives",
@@ -6473,7 +6398,7 @@ dependencies = [
  "futures-timer",
  "kvdb",
  "kvdb-memorydb",
- "lru 0.8.0",
+ "lru",
  "parity-scale-codec",
  "polkadot-node-primitives",
  "polkadot-node-subsystem",
@@ -6757,10 +6682,11 @@ dependencies = [
  "futures",
  "itertools",
  "kvdb",
+ "kvdb-memorydb",
  "kvdb-shared-tests",
  "lazy_static",
  "log",
- "lru 0.8.0",
+ "lru",
  "parity-db",
  "parity-scale-codec",
  "parity-util-mem",
@@ -6794,7 +6720,7 @@ dependencies = [
  "femme",
  "futures",
  "futures-timer",
- "lru 0.8.0",
+ "lru",
  "orchestra",
  "parity-util-mem",
  "parking_lot 0.12.1",
@@ -7029,6 +6955,7 @@ dependencies = [
  "pallet-election-provider-multi-phase",
  "pallet-session",
  "pallet-staking",
+ "pallet-staking-reward-fn",
  "pallet-timestamp",
  "pallet-transaction-payment",
  "pallet-treasury",
@@ -7149,7 +7076,7 @@ dependencies = [
  "kvdb",
  "kvdb-rocksdb",
  "log",
- "lru 0.8.0",
+ "lru",
  "pallet-babe",
  "pallet-im-online",
  "pallet-staking",
@@ -7476,7 +7403,7 @@ version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "685404d509889fade3e86fe3a5803bca2ec09b0c0778d5ada6ec8bf7a8de5259"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "log",
  "wepoll-ffi",
@@ -7500,7 +7427,7 @@ version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8419d2b623c7c0896ff2d5d96e2cb4ede590fed28fcc34934f4c33c036e620a1"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpufeatures",
  "opaque-debug 0.3.0",
  "universal-hash",
@@ -7513,7 +7440,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55f35f865aa964be21fcde114cbd1cfbd9bf8a471460ed965b0f84f96c711401"
 dependencies = [
  "backtrace",
- "cfg-if 1.0.0",
+ "cfg-if",
  "findshlibs",
  "lazy_static",
  "libc",
@@ -7652,7 +7579,7 @@ version = "0.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b7f64969ffd5dd8f39bd57a68ac53c163a095ed9d0fb707146da1b27025a3504"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "fnv",
  "lazy_static",
  "memchr",
@@ -7667,7 +7594,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "83cd1b99916654a69008fd66b4f9397fbe08e6e51dfe23d4417acf5d3b8cb87c"
 dependencies = [
  "dtoa",
- "itoa 1.0.1",
+ "itoa",
  "parking_lot 0.12.1",
  "prometheus-client-derive-text-encode",
 ]
@@ -8063,7 +7990,7 @@ dependencies = [
 [[package]]
 name = "remote-externalities"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "env_logger 0.9.0",
  "log",
@@ -8402,7 +8329,7 @@ dependencies = [
 [[package]]
 name = "sc-allocator"
 version = "4.1.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "sp-core",
@@ -8413,7 +8340,7 @@ dependencies = [
 [[package]]
 name = "sc-authority-discovery"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -8440,7 +8367,7 @@ dependencies = [
 [[package]]
 name = "sc-basic-authorship"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "futures-timer",
@@ -8463,7 +8390,7 @@ dependencies = [
 [[package]]
 name = "sc-block-builder"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "sc-client-api",
@@ -8479,10 +8406,10 @@ dependencies = [
 [[package]]
 name = "sc-chain-spec"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "impl-trait-for-tuples",
- "memmap2 0.5.0",
+ "memmap2",
  "parity-scale-codec",
  "sc-chain-spec-derive",
  "sc-network-common",
@@ -8496,7 +8423,7 @@ dependencies = [
 [[package]]
 name = "sc-chain-spec-derive"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro-crate",
  "proc-macro2",
@@ -8507,7 +8434,7 @@ dependencies = [
 [[package]]
 name = "sc-cli"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "chrono",
@@ -8547,7 +8474,7 @@ dependencies = [
 [[package]]
 name = "sc-client-api"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "fnv",
  "futures",
@@ -8575,7 +8502,7 @@ dependencies = [
 [[package]]
 name = "sc-client-db"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "hash-db",
  "kvdb",
@@ -8600,7 +8527,7 @@ dependencies = [
 [[package]]
 name = "sc-consensus"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -8624,19 +8551,18 @@ dependencies = [
 [[package]]
 name = "sc-consensus-babe"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "fork-tree",
  "futures",
  "log",
  "merlin",
- "num-bigint 0.2.6",
- "num-rational 0.2.4",
+ "num-bigint",
+ "num-rational",
  "num-traits",
  "parity-scale-codec",
  "parking_lot 0.12.1",
- "rand 0.7.3",
  "sc-client-api",
  "sc-consensus",
  "sc-consensus-epochs",
@@ -8666,7 +8592,7 @@ dependencies = [
 [[package]]
 name = "sc-consensus-babe-rpc"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "jsonrpsee",
@@ -8688,7 +8614,7 @@ dependencies = [
 [[package]]
 name = "sc-consensus-epochs"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "fork-tree",
  "parity-scale-codec",
@@ -8701,7 +8627,7 @@ dependencies = [
 [[package]]
 name = "sc-consensus-slots"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -8725,10 +8651,10 @@ dependencies = [
 [[package]]
 name = "sc-executor"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "lazy_static",
- "lru 0.7.8",
+ "lru",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "sc-executor-common",
@@ -8752,7 +8678,7 @@ dependencies = [
 [[package]]
 name = "sc-executor-common"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "environmental",
  "parity-scale-codec",
@@ -8768,7 +8694,7 @@ dependencies = [
 [[package]]
 name = "sc-executor-wasmi"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "parity-scale-codec",
@@ -8783,9 +8709,9 @@ dependencies = [
 [[package]]
 name = "sc-executor-wasmtime"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "libc",
  "log",
  "once_cell",
@@ -8803,7 +8729,7 @@ dependencies = [
 [[package]]
 name = "sc-finality-grandpa"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ahash",
  "array-bytes",
@@ -8844,7 +8770,7 @@ dependencies = [
 [[package]]
 name = "sc-finality-grandpa-rpc"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "finality-grandpa",
  "futures",
@@ -8865,7 +8791,7 @@ dependencies = [
 [[package]]
 name = "sc-informant"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ansi_term",
  "futures",
@@ -8882,7 +8808,7 @@ dependencies = [
 [[package]]
 name = "sc-keystore"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "async-trait",
@@ -8897,7 +8823,7 @@ dependencies = [
 [[package]]
 name = "sc-network"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "async-trait",
@@ -8915,7 +8841,7 @@ dependencies = [
  "linked-hash-map",
  "linked_hash_set",
  "log",
- "lru 0.7.8",
+ "lru",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "pin-project",
@@ -8944,7 +8870,7 @@ dependencies = [
 [[package]]
 name = "sc-network-bitswap"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "cid",
  "futures",
@@ -8964,7 +8890,7 @@ dependencies = [
 [[package]]
 name = "sc-network-common"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "bitflags",
@@ -8990,14 +8916,14 @@ dependencies = [
 [[package]]
 name = "sc-network-gossip"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ahash",
  "futures",
  "futures-timer",
  "libp2p",
  "log",
- "lru 0.7.8",
+ "lru",
  "sc-network-common",
  "sc-peerset",
  "sp-runtime",
@@ -9008,7 +8934,7 @@ dependencies = [
 [[package]]
 name = "sc-network-light"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "futures",
@@ -9029,14 +8955,14 @@ dependencies = [
 [[package]]
 name = "sc-network-sync"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "fork-tree",
  "futures",
  "libp2p",
  "log",
- "lru 0.7.8",
+ "lru",
  "mockall",
  "parity-scale-codec",
  "prost",
@@ -9059,7 +8985,7 @@ dependencies = [
 [[package]]
 name = "sc-network-transactions"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "futures",
@@ -9078,7 +9004,7 @@ dependencies = [
 [[package]]
 name = "sc-offchain"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "bytes",
@@ -9108,7 +9034,7 @@ dependencies = [
 [[package]]
 name = "sc-peerset"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "libp2p",
@@ -9121,7 +9047,7 @@ dependencies = [
 [[package]]
 name = "sc-proposer-metrics"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "substrate-prometheus-endpoint",
@@ -9130,7 +9056,7 @@ dependencies = [
 [[package]]
 name = "sc-rpc"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "hash-db",
@@ -9160,7 +9086,7 @@ dependencies = [
 [[package]]
 name = "sc-rpc-api"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "jsonrpsee",
@@ -9183,7 +9109,7 @@ dependencies = [
 [[package]]
 name = "sc-rpc-server"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "jsonrpsee",
@@ -9196,7 +9122,7 @@ dependencies = [
 [[package]]
 name = "sc-rpc-spec-v2"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "hex",
@@ -9215,7 +9141,7 @@ dependencies = [
 [[package]]
 name = "sc-service"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "directories",
@@ -9286,7 +9212,7 @@ dependencies = [
 [[package]]
 name = "sc-state-db"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "parity-scale-codec",
@@ -9300,7 +9226,7 @@ dependencies = [
 [[package]]
 name = "sc-sync-state-rpc"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "jsonrpsee",
  "parity-scale-codec",
@@ -9319,7 +9245,7 @@ dependencies = [
 [[package]]
 name = "sc-sysinfo"
 version = "6.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "libc",
@@ -9338,7 +9264,7 @@ dependencies = [
 [[package]]
 name = "sc-telemetry"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "chrono",
  "futures",
@@ -9356,7 +9282,7 @@ dependencies = [
 [[package]]
 name = "sc-tracing"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ansi_term",
  "atty",
@@ -9387,7 +9313,7 @@ dependencies = [
 [[package]]
 name = "sc-tracing-proc-macro"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro-crate",
  "proc-macro2",
@@ -9398,7 +9324,7 @@ dependencies = [
 [[package]]
 name = "sc-transaction-pool"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -9425,7 +9351,7 @@ dependencies = [
 [[package]]
 name = "sc-transaction-pool-api"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -9439,7 +9365,7 @@ dependencies = [
 [[package]]
 name = "sc-utils"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "futures-timer",
@@ -9456,7 +9382,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c46be926081c9f4dd5dd9b6f1d3e3229f2360bc6502dd8836f84a93b7c75e99a"
 dependencies = [
  "bitvec",
- "cfg-if 1.0.0",
+ "cfg-if",
  "derive_more",
  "parity-scale-codec",
  "scale-info-derive",
@@ -9654,7 +9580,7 @@ version = "1.0.85"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e55a28e3aaef9d5ce0506d0a14dbba8054ddc7e499ef522dd8b26859ec9d4a44"
 dependencies = [
- "itoa 1.0.1",
+ "itoa",
  "ryu",
  "serde",
 ]
@@ -9675,7 +9601,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d3491c14715ca2294c4d6a88f15e84739788c1d030eed8c110436aafdaa2f3fd"
 dependencies = [
  "form_urlencoded",
- "itoa 1.0.1",
+ "itoa",
  "ryu",
  "serde",
 ]
@@ -9699,7 +9625,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "99cd6713db3cf16b6c84e06321e049a9b9f699826e16096d23bbcc44d15d51a6"
 dependencies = [
  "block-buffer 0.9.0",
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpufeatures",
  "digest 0.9.0",
  "opaque-debug 0.3.0",
@@ -9711,7 +9637,7 @@ version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "028f48d513f9678cda28f6e4064755b3fbb2af6acd672f2c209b62323f7aea0f"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpufeatures",
  "digest 0.10.3",
 ]
@@ -9735,7 +9661,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b69f9a4c9740d74c5baa3fd2e547f9525fa8088a8a958e0ca2409a514e33f5fa"
 dependencies = [
  "block-buffer 0.9.0",
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpufeatures",
  "digest 0.9.0",
  "opaque-debug 0.3.0",
@@ -9747,7 +9673,7 @@ version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55deaec60f81eefe3cce0dc50bda92d6d8e88f2a27df7c5033b42afeb1ed2676"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpufeatures",
  "digest 0.10.3",
 ]
@@ -9920,7 +9846,7 @@ dependencies = [
 [[package]]
 name = "sp-api"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "hash-db",
  "log",
@@ -9938,7 +9864,7 @@ dependencies = [
 [[package]]
 name = "sp-api-proc-macro"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "blake2",
  "proc-macro-crate",
@@ -9950,7 +9876,7 @@ dependencies = [
 [[package]]
 name = "sp-application-crypto"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -9963,7 +9889,7 @@ dependencies = [
 [[package]]
 name = "sp-arithmetic"
 version = "5.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "integer-sqrt",
  "num-traits",
@@ -9978,7 +9904,7 @@ dependencies = [
 [[package]]
 name = "sp-authority-discovery"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -9991,7 +9917,7 @@ dependencies = [
 [[package]]
 name = "sp-authorship"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "parity-scale-codec",
@@ -10003,7 +9929,7 @@ dependencies = [
 [[package]]
 name = "sp-block-builder"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "sp-api",
@@ -10015,11 +9941,11 @@ dependencies = [
 [[package]]
 name = "sp-blockchain"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "log",
- "lru 0.7.8",
+ "lru",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "sp-api",
@@ -10033,7 +9959,7 @@ dependencies = [
 [[package]]
 name = "sp-consensus"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -10052,7 +9978,7 @@ dependencies = [
 [[package]]
 name = "sp-consensus-babe"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "merlin",
@@ -10075,7 +10001,7 @@ dependencies = [
 [[package]]
 name = "sp-consensus-slots"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -10089,7 +10015,7 @@ dependencies = [
 [[package]]
 name = "sp-consensus-vrf"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -10102,7 +10028,7 @@ dependencies = [
 [[package]]
 name = "sp-core"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "base58",
@@ -10148,7 +10074,7 @@ dependencies = [
 [[package]]
 name = "sp-core-hashing"
 version = "4.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "blake2",
  "byteorder",
@@ -10162,7 +10088,7 @@ dependencies = [
 [[package]]
 name = "sp-core-hashing-proc-macro"
 version = "5.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -10173,7 +10099,7 @@ dependencies = [
 [[package]]
 name = "sp-database"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "kvdb",
  "parking_lot 0.12.1",
@@ -10182,7 +10108,7 @@ dependencies = [
 [[package]]
 name = "sp-debug-derive"
 version = "4.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -10192,7 +10118,7 @@ dependencies = [
 [[package]]
 name = "sp-externalities"
 version = "0.12.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "environmental",
  "parity-scale-codec",
@@ -10203,7 +10129,7 @@ dependencies = [
 [[package]]
 name = "sp-finality-grandpa"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "finality-grandpa",
  "log",
@@ -10221,7 +10147,7 @@ dependencies = [
 [[package]]
 name = "sp-inherents"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "impl-trait-for-tuples",
@@ -10235,7 +10161,7 @@ dependencies = [
 [[package]]
 name = "sp-io"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "bytes",
  "futures",
@@ -10261,7 +10187,7 @@ dependencies = [
 [[package]]
 name = "sp-keyring"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "lazy_static",
  "sp-core",
@@ -10272,7 +10198,7 @@ dependencies = [
 [[package]]
 name = "sp-keystore"
 version = "0.12.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures",
@@ -10289,7 +10215,7 @@ dependencies = [
 [[package]]
 name = "sp-maybe-compressed-blob"
 version = "4.1.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "thiserror",
  "zstd",
@@ -10298,7 +10224,7 @@ dependencies = [
 [[package]]
 name = "sp-mmr-primitives"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "parity-scale-codec",
@@ -10309,12 +10235,13 @@ dependencies = [
  "sp-debug-derive",
  "sp-runtime",
  "sp-std",
+ "thiserror",
 ]
 
 [[package]]
 name = "sp-npos-elections"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -10328,7 +10255,7 @@ dependencies = [
 [[package]]
 name = "sp-offchain"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "sp-api",
  "sp-core",
@@ -10338,7 +10265,7 @@ dependencies = [
 [[package]]
 name = "sp-panic-handler"
 version = "4.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "backtrace",
  "lazy_static",
@@ -10348,7 +10275,7 @@ dependencies = [
 [[package]]
 name = "sp-rpc"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "rustc-hash",
  "serde",
@@ -10358,7 +10285,7 @@ dependencies = [
 [[package]]
 name = "sp-runtime"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "either",
  "hash256-std-hasher",
@@ -10381,7 +10308,7 @@ dependencies = [
 [[package]]
 name = "sp-runtime-interface"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "bytes",
  "impl-trait-for-tuples",
@@ -10399,7 +10326,7 @@ dependencies = [
 [[package]]
 name = "sp-runtime-interface-proc-macro"
 version = "5.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "Inflector",
  "proc-macro-crate",
@@ -10411,7 +10338,7 @@ dependencies = [
 [[package]]
 name = "sp-sandbox"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "parity-scale-codec",
@@ -10425,7 +10352,7 @@ dependencies = [
 [[package]]
 name = "sp-session"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -10439,7 +10366,7 @@ dependencies = [
 [[package]]
 name = "sp-staking"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "scale-info",
@@ -10450,7 +10377,7 @@ dependencies = [
 [[package]]
 name = "sp-state-machine"
 version = "0.12.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "hash-db",
  "log",
@@ -10472,12 +10399,12 @@ dependencies = [
 [[package]]
 name = "sp-std"
 version = "4.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 
 [[package]]
 name = "sp-storage"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "impl-serde",
  "parity-scale-codec",
@@ -10490,7 +10417,7 @@ dependencies = [
 [[package]]
 name = "sp-tasks"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "log",
  "sp-core",
@@ -10503,7 +10430,7 @@ dependencies = [
 [[package]]
 name = "sp-timestamp"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "futures-timer",
@@ -10519,7 +10446,7 @@ dependencies = [
 [[package]]
 name = "sp-tracing"
 version = "5.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "sp-std",
@@ -10531,7 +10458,7 @@ dependencies = [
 [[package]]
 name = "sp-transaction-pool"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "sp-api",
  "sp-runtime",
@@ -10540,7 +10467,7 @@ dependencies = [
 [[package]]
 name = "sp-transaction-storage-proof"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "log",
@@ -10556,13 +10483,13 @@ dependencies = [
 [[package]]
 name = "sp-trie"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ahash",
  "hash-db",
  "hashbrown",
  "lazy_static",
- "lru 0.7.8",
+ "lru",
  "memory-db",
  "nohash-hasher",
  "parity-scale-codec",
@@ -10579,7 +10506,7 @@ dependencies = [
 [[package]]
 name = "sp-version"
 version = "5.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "impl-serde",
  "parity-scale-codec",
@@ -10596,7 +10523,7 @@ dependencies = [
 [[package]]
 name = "sp-version-proc-macro"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "parity-scale-codec",
  "proc-macro2",
@@ -10607,7 +10534,7 @@ dependencies = [
 [[package]]
 name = "sp-wasm-interface"
 version = "6.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "impl-trait-for-tuples",
  "log",
@@ -10620,7 +10547,7 @@ dependencies = [
 [[package]]
 name = "sp-weights"
 version = "4.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "impl-trait-for-tuples",
  "parity-scale-codec",
@@ -10835,7 +10762,7 @@ dependencies = [
 [[package]]
 name = "substrate-build-script-utils"
 version = "3.0.0"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "platforms",
 ]
@@ -10843,7 +10770,7 @@ dependencies = [
 [[package]]
 name = "substrate-frame-rpc-system"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "frame-system-rpc-runtime-api",
  "futures",
@@ -10864,7 +10791,7 @@ dependencies = [
 [[package]]
 name = "substrate-prometheus-endpoint"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures-util",
  "hyper",
@@ -10877,7 +10804,7 @@ dependencies = [
 [[package]]
 name = "substrate-rpc-client"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "async-trait",
  "jsonrpsee",
@@ -10890,7 +10817,7 @@ dependencies = [
 [[package]]
 name = "substrate-state-trie-migration-rpc"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "jsonrpsee",
  "log",
@@ -10911,7 +10838,7 @@ dependencies = [
 [[package]]
 name = "substrate-test-client"
 version = "2.0.1"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "array-bytes",
  "async-trait",
@@ -10937,7 +10864,7 @@ dependencies = [
 [[package]]
 name = "substrate-test-utils"
 version = "4.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "futures",
  "substrate-test-utils-derive",
@@ -10947,7 +10874,7 @@ dependencies = [
 [[package]]
 name = "substrate-test-utils-derive"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "proc-macro-crate",
  "proc-macro2",
@@ -10958,7 +10885,7 @@ dependencies = [
 [[package]]
 name = "substrate-wasm-builder"
 version = "5.0.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "ansi_term",
  "build-helper",
@@ -10994,7 +10921,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e92a52f07eed9afba3d6f883652cde7cd75fcf327dd44e84f210958379158737"
 dependencies = [
  "debugid",
- "memmap2 0.5.0",
+ "memmap2",
  "stable_deref_trait",
  "uuid",
 ]
@@ -11072,7 +10999,7 @@ version = "3.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5cdb1ef4eaeeaddc8fbd371e5017057064af0911902ef36b39801f67cc6d79e4"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "fastrand",
  "libc",
  "redox_syscall",
@@ -11470,7 +11397,7 @@ version = "0.1.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a400e31aa60b9d44a52a8ee0343b5b18566b03a8321e0d321f695cf56e940160"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "pin-project-lite 0.2.7",
  "tracing-attributes",
  "tracing-core",
@@ -11620,7 +11547,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4f7f83d1e4a0e4358ac54c5c3681e5d7da5efc5a7a632c90bb6d6669ddd9bc26"
 dependencies = [
  "async-trait",
- "cfg-if 1.0.0",
+ "cfg-if",
  "data-encoding",
  "enum-as-inner",
  "futures-channel",
@@ -11643,7 +11570,7 @@ version = "0.22.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aff21aa4dcefb0a1afbfac26deb0adc93888c7d295fb63ab273ef276ba2b7cfe"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "futures-util",
  "ipconfig",
  "lazy_static",
@@ -11665,7 +11592,7 @@ checksum = "59547bce71d9c38b83d9c0e92b6066c4253371f15005def0c30d9657f50c7642"
 [[package]]
 name = "try-runtime-cli"
 version = "0.10.0-dev"
-source = "git+https://github.com/paritytech/substrate?branch=master#3cd6db7907bd0efc9e4299b168196d97651dfc25"
+source = "git+https://github.com/paritytech/substrate?branch=master#a6da808575fe403ab2bd7f6cd009896cdc6fd71a"
 dependencies = [
  "clap",
  "frame-try-runtime",
@@ -11736,7 +11663,7 @@ version = "1.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "97fee6b57c6a41524a810daee9286c02d7752c4253064d0b05472833a438f675"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "digest 0.10.3",
  "rand 0.8.5",
  "static_assertions",
@@ -11958,7 +11885,7 @@ version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "632f73e236b219150ea279196e54e610f5dbafa5d61786303d4da54f84e47fce"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "serde",
  "serde_json",
  "wasm-bindgen-macro",
@@ -11985,7 +11912,7 @@ version = "0.4.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8e8d7523cb1f2a4c96c1317ca690031b714a51cc14e05f712446691f413f5d39"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
  "js-sys",
  "wasm-bindgen",
  "web-sys",
@@ -12114,7 +12041,7 @@ dependencies = [
  "downcast-rs",
  "libm",
  "memory_units",
- "num-rational 0.4.0",
+ "num-rational",
  "num-traits",
 ]
 
@@ -12135,7 +12062,7 @@ checksum = "8a10dc9784d8c3a33c970e3939180424955f08af2e7f20368ec02685a0e8f065"
 dependencies = [
  "anyhow",
  "bincode",
- "cfg-if 1.0.0",
+ "cfg-if",
  "indexmap",
  "libc",
  "log",
@@ -12161,7 +12088,7 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee4dbdc6daf68528cad1275ac91e3f51848ce9824385facc94c759f529decdf8"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if",
 ]
 
 [[package]]
@@ -12233,7 +12160,7 @@ dependencies = [
  "addr2line",
  "anyhow",
  "bincode",
- "cfg-if 1.0.0",
+ "cfg-if",
  "cpp_demangle",
  "gimli",
  "log",
@@ -12268,7 +12195,7 @@ checksum = "ae79e0515160bd5abee5df50a16c4eb8db9f71b530fc988ae1d9ce34dcb8dd01"
 dependencies = [
  "anyhow",
  "cc",
- "cfg-if 1.0.0",
+ "cfg-if",
  "indexmap",
  "libc",
  "log",
diff --git a/node/client/src/lib.rs b/node/client/src/lib.rs
index ae5d6b4d05db..d2c119ba04a8 100644
--- a/node/client/src/lib.rs
+++ b/node/client/src/lib.rs
@@ -327,7 +327,7 @@ impl UsageProvider<Block> for Client {
 impl sc_client_api::BlockBackend<Block> for Client {
 	fn block_body(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 	) -> sp_blockchain::Result<Option<Vec<<Block as BlockT>::Extrinsic>>> {
 		with_client! {
 			self,
@@ -360,7 +360,7 @@ impl sc_client_api::BlockBackend<Block> for Client {
 
 	fn justifications(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 	) -> sp_blockchain::Result<Option<Justifications>> {
 		with_client! {
 			self,
@@ -386,7 +386,7 @@ impl sc_client_api::BlockBackend<Block> for Client {
 
 	fn indexed_transaction(
 		&self,
-		id: &<Block as BlockT>::Hash,
+		id: <Block as BlockT>::Hash,
 	) -> sp_blockchain::Result<Option<Vec<u8>>> {
 		with_client! {
 			self,
@@ -399,7 +399,7 @@ impl sc_client_api::BlockBackend<Block> for Client {
 
 	fn block_indexed_body(
 		&self,
-		id: &<Block as BlockT>::Hash,
+		id: <Block as BlockT>::Hash,
 	) -> sp_blockchain::Result<Option<Vec<Vec<u8>>>> {
 		with_client! {
 			self,
@@ -424,7 +424,7 @@ impl sc_client_api::BlockBackend<Block> for Client {
 impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 	fn storage(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		key: &StorageKey,
 	) -> sp_blockchain::Result<Option<StorageData>> {
 		with_client! {
@@ -438,7 +438,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn storage_keys(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		key_prefix: &StorageKey,
 	) -> sp_blockchain::Result<Vec<StorageKey>> {
 		with_client! {
@@ -452,7 +452,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn storage_hash(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		key: &StorageKey,
 	) -> sp_blockchain::Result<Option<<Block as BlockT>::Hash>> {
 		with_client! {
@@ -466,7 +466,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn storage_pairs(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		key_prefix: &StorageKey,
 	) -> sp_blockchain::Result<Vec<(StorageKey, StorageData)>> {
 		with_client! {
@@ -480,7 +480,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn storage_keys_iter<'a>(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		prefix: Option<&'a StorageKey>,
 		start_key: Option<&StorageKey>,
 	) -> sp_blockchain::Result<
@@ -497,7 +497,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn child_storage(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		child_info: &ChildInfo,
 		key: &StorageKey,
 	) -> sp_blockchain::Result<Option<StorageData>> {
@@ -512,7 +512,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn child_storage_keys(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		child_info: &ChildInfo,
 		key_prefix: &StorageKey,
 	) -> sp_blockchain::Result<Vec<StorageKey>> {
@@ -527,7 +527,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn child_storage_keys_iter<'a>(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		child_info: ChildInfo,
 		prefix: Option<&'a StorageKey>,
 		start_key: Option<&StorageKey>,
@@ -545,7 +545,7 @@ impl sc_client_api::StorageProvider<Block, crate::FullBackend> for Client {
 
 	fn child_storage_hash(
 		&self,
-		hash: &<Block as BlockT>::Hash,
+		hash: <Block as BlockT>::Hash,
 		child_info: &ChildInfo,
 		key: &StorageKey,
 	) -> sp_blockchain::Result<Option<<Block as BlockT>::Hash>> {
diff --git a/node/core/approval-voting/src/approval_db/v1/mod.rs b/node/core/approval-voting/src/approval_db/v1/mod.rs
index 03b7aa68f134..858bcb8c36fe 100644
--- a/node/core/approval-voting/src/approval_db/v1/mod.rs
+++ b/node/core/approval-voting/src/approval_db/v1/mod.rs
@@ -90,41 +90,45 @@ impl Backend for DbBackend {
 			match op {
 				BackendWriteOp::WriteStoredBlockRange(stored_block_range) => {
 					tx.put_vec(
-						self.config.col_data,
+						self.config.col_approval_data,
 						&STORED_BLOCKS_KEY,
 						stored_block_range.encode(),
 					);
 				},
 				BackendWriteOp::DeleteStoredBlockRange => {
-					tx.delete(self.config.col_data, &STORED_BLOCKS_KEY);
+					tx.delete(self.config.col_approval_data, &STORED_BLOCKS_KEY);
 				},
 				BackendWriteOp::WriteBlocksAtHeight(h, blocks) => {
-					tx.put_vec(self.config.col_data, &blocks_at_height_key(h), blocks.encode());
+					tx.put_vec(
+						self.config.col_approval_data,
+						&blocks_at_height_key(h),
+						blocks.encode(),
+					);
 				},
 				BackendWriteOp::DeleteBlocksAtHeight(h) => {
-					tx.delete(self.config.col_data, &blocks_at_height_key(h));
+					tx.delete(self.config.col_approval_data, &blocks_at_height_key(h));
 				},
 				BackendWriteOp::WriteBlockEntry(block_entry) => {
 					let block_entry: BlockEntry = block_entry.into();
 					tx.put_vec(
-						self.config.col_data,
+						self.config.col_approval_data,
 						&block_entry_key(&block_entry.block_hash),
 						block_entry.encode(),
 					);
 				},
 				BackendWriteOp::DeleteBlockEntry(hash) => {
-					tx.delete(self.config.col_data, &block_entry_key(&hash));
+					tx.delete(self.config.col_approval_data, &block_entry_key(&hash));
 				},
 				BackendWriteOp::WriteCandidateEntry(candidate_entry) => {
 					let candidate_entry: CandidateEntry = candidate_entry.into();
 					tx.put_vec(
-						self.config.col_data,
+						self.config.col_approval_data,
 						&candidate_entry_key(&candidate_entry.candidate.hash()),
 						candidate_entry.encode(),
 					);
 				},
 				BackendWriteOp::DeleteCandidateEntry(candidate_hash) => {
-					tx.delete(self.config.col_data, &candidate_entry_key(&candidate_hash));
+					tx.delete(self.config.col_approval_data, &candidate_entry_key(&candidate_hash));
 				},
 			}
 		}
@@ -149,7 +153,9 @@ pub type Bitfield = BitVec<u8, BitOrderLsb0>;
 #[derive(Debug, Clone, Copy)]
 pub struct Config {
 	/// The column family in the database where data is stored.
-	pub col_data: u32,
+	pub col_approval_data: u32,
+	/// The column of the database where rolling session window data is stored.
+	pub col_session_data: u32,
 }
 
 /// Details pertaining to our assignment on a block.
@@ -243,10 +249,10 @@ pub type Result<T> = std::result::Result<T, Error>;
 
 pub(crate) fn load_decode<D: Decode>(
 	store: &dyn Database,
-	col_data: u32,
+	col_approval_data: u32,
 	key: &[u8],
 ) -> Result<Option<D>> {
-	match store.get(col_data, key)? {
+	match store.get(col_approval_data, key)? {
 		None => Ok(None),
 		Some(raw) => D::decode(&mut &raw[..]).map(Some).map_err(Into::into),
 	}
@@ -303,7 +309,7 @@ pub fn load_stored_blocks(
 	store: &dyn Database,
 	config: &Config,
 ) -> SubsystemResult<Option<StoredBlockRange>> {
-	load_decode(store, config.col_data, STORED_BLOCKS_KEY)
+	load_decode(store, config.col_approval_data, STORED_BLOCKS_KEY)
 		.map_err(|e| SubsystemError::with_origin("approval-voting", e))
 }
 
@@ -313,7 +319,7 @@ pub fn load_blocks_at_height(
 	config: &Config,
 	block_number: &BlockNumber,
 ) -> SubsystemResult<Vec<Hash>> {
-	load_decode(store, config.col_data, &blocks_at_height_key(*block_number))
+	load_decode(store, config.col_approval_data, &blocks_at_height_key(*block_number))
 		.map(|x| x.unwrap_or_default())
 		.map_err(|e| SubsystemError::with_origin("approval-voting", e))
 }
@@ -324,7 +330,7 @@ pub fn load_block_entry(
 	config: &Config,
 	block_hash: &Hash,
 ) -> SubsystemResult<Option<BlockEntry>> {
-	load_decode(store, config.col_data, &block_entry_key(block_hash))
+	load_decode(store, config.col_approval_data, &block_entry_key(block_hash))
 		.map(|u: Option<BlockEntry>| u.map(|v| v.into()))
 		.map_err(|e| SubsystemError::with_origin("approval-voting", e))
 }
@@ -335,7 +341,7 @@ pub fn load_candidate_entry(
 	config: &Config,
 	candidate_hash: &CandidateHash,
 ) -> SubsystemResult<Option<CandidateEntry>> {
-	load_decode(store, config.col_data, &candidate_entry_key(candidate_hash))
+	load_decode(store, config.col_approval_data, &candidate_entry_key(candidate_hash))
 		.map(|u: Option<CandidateEntry>| u.map(|v| v.into()))
 		.map_err(|e| SubsystemError::with_origin("approval-voting", e))
 }
diff --git a/node/core/approval-voting/src/approval_db/v1/tests.rs b/node/core/approval-voting/src/approval_db/v1/tests.rs
index 548c64bcef03..06923c6a539f 100644
--- a/node/core/approval-voting/src/approval_db/v1/tests.rs
+++ b/node/core/approval-voting/src/approval_db/v1/tests.rs
@@ -28,9 +28,12 @@ use std::{collections::HashMap, sync::Arc};
 use ::test_helpers::{dummy_candidate_receipt, dummy_candidate_receipt_bad_sig, dummy_hash};
 
 const DATA_COL: u32 = 0;
-const NUM_COLUMNS: u32 = 1;
+const SESSION_DATA_COL: u32 = 1;
 
-const TEST_CONFIG: Config = Config { col_data: DATA_COL };
+const NUM_COLUMNS: u32 = 2;
+
+const TEST_CONFIG: Config =
+	Config { col_approval_data: DATA_COL, col_session_data: SESSION_DATA_COL };
 
 fn make_db() -> (DbBackend, Arc<dyn Database>) {
 	let db = kvdb_memorydb::create(NUM_COLUMNS);
diff --git a/node/core/approval-voting/src/import.rs b/node/core/approval-voting/src/import.rs
index df713143750f..20629dd022d4 100644
--- a/node/core/approval-voting/src/import.rs
+++ b/node/core/approval-voting/src/import.rs
@@ -632,14 +632,15 @@ pub(crate) mod tests {
 	pub(crate) use sp_runtime::{Digest, DigestItem};
 	use std::{pin::Pin, sync::Arc};
 
-	use crate::{
-		approval_db::v1::Config as DatabaseConfig, criteria, BlockEntry, APPROVAL_SESSIONS,
-	};
+	use crate::{approval_db::v1::Config as DatabaseConfig, criteria, BlockEntry};
 
 	const DATA_COL: u32 = 0;
-	const NUM_COLUMNS: u32 = 1;
+	const SESSION_DATA_COL: u32 = 1;
+
+	const NUM_COLUMNS: u32 = 2;
 
-	const TEST_CONFIG: DatabaseConfig = DatabaseConfig { col_data: DATA_COL };
+	const TEST_CONFIG: DatabaseConfig =
+		DatabaseConfig { col_approval_data: DATA_COL, col_session_data: SESSION_DATA_COL };
 	#[derive(Default)]
 	struct MockClock;
 
@@ -654,22 +655,23 @@ pub(crate) mod tests {
 	}
 
 	fn blank_state() -> State {
+		let db = kvdb_memorydb::create(NUM_COLUMNS);
+		let db = polkadot_node_subsystem_util::database::kvdb_impl::DbAdapter::new(db, &[]);
+		let db: Arc<dyn Database> = Arc::new(db);
 		State {
 			session_window: None,
 			keystore: Arc::new(LocalKeystore::in_memory()),
 			slot_duration_millis: 6_000,
 			clock: Box::new(MockClock::default()),
 			assignment_criteria: Box::new(MockAssignmentCriteria),
+			db,
+			db_config: TEST_CONFIG,
 		}
 	}
 
 	fn single_session_state(index: SessionIndex, info: SessionInfo) -> State {
 		State {
-			session_window: Some(RollingSessionWindow::with_session_info(
-				APPROVAL_SESSIONS,
-				index,
-				vec![info],
-			)),
+			session_window: Some(RollingSessionWindow::with_session_info(index, vec![info])),
 			..blank_state()
 		}
 	}
@@ -782,11 +784,8 @@ pub(crate) mod tests {
 				.map(|(r, c, g)| (r.hash(), r.clone(), *c, *g))
 				.collect::<Vec<_>>();
 
-			let session_window = RollingSessionWindow::with_session_info(
-				APPROVAL_SESSIONS,
-				session,
-				vec![session_info],
-			);
+			let session_window =
+				RollingSessionWindow::with_session_info(session, vec![session_info]);
 
 			let header = header.clone();
 			Box::pin(async move {
@@ -891,11 +890,8 @@ pub(crate) mod tests {
 			.collect::<Vec<_>>();
 
 		let test_fut = {
-			let session_window = RollingSessionWindow::with_session_info(
-				APPROVAL_SESSIONS,
-				session,
-				vec![session_info],
-			);
+			let session_window =
+				RollingSessionWindow::with_session_info(session, vec![session_info]);
 
 			let header = header.clone();
 			Box::pin(async move {
@@ -1089,11 +1085,8 @@ pub(crate) mod tests {
 				.map(|(r, c, g)| (r.hash(), r.clone(), *c, *g))
 				.collect::<Vec<_>>();
 
-			let session_window = Some(RollingSessionWindow::with_session_info(
-				APPROVAL_SESSIONS,
-				session,
-				vec![session_info],
-			));
+			let session_window =
+				Some(RollingSessionWindow::with_session_info(session, vec![session_info]));
 
 			let header = header.clone();
 			Box::pin(async move {
@@ -1304,38 +1297,6 @@ pub(crate) mod tests {
 				}
 			);
 
-			// Caching of sesssions needs sessoion of first unfinalied block.
-			assert_matches!(
-				handle.recv().await,
-				AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
-					s_tx,
-				)) => {
-					let _ = s_tx.send(Ok(header.number));
-				}
-			);
-
-			assert_matches!(
-				handle.recv().await,
-				AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
-					block_number,
-					s_tx,
-				)) => {
-					assert_eq!(block_number, header.number);
-					let _ = s_tx.send(Ok(Some(header.hash())));
-				}
-			);
-
-			assert_matches!(
-				handle.recv().await,
-				AllMessages::RuntimeApi(RuntimeApiMessage::Request(
-					h,
-					RuntimeApiRequest::SessionIndexForChild(s_tx),
-				)) => {
-					assert_eq!(h, header.hash());
-					let _ = s_tx.send(Ok(session));
-				}
-			);
-
 			// determine_new_blocks exits early as the parent_hash is in the DB
 
 			assert_matches!(
diff --git a/node/core/approval-voting/src/lib.rs b/node/core/approval-voting/src/lib.rs
index e9757071f15e..b96992df2c88 100644
--- a/node/core/approval-voting/src/lib.rs
+++ b/node/core/approval-voting/src/lib.rs
@@ -44,8 +44,7 @@ use polkadot_node_subsystem_util::{
 	database::Database,
 	metrics::{self, prometheus},
 	rolling_session_window::{
-		new_session_window_size, RollingSessionWindow, SessionWindowSize, SessionWindowUpdate,
-		SessionsUnavailable,
+		DatabaseParams, RollingSessionWindow, SessionWindowUpdate, SessionsUnavailable,
 	},
 	TimeoutExt,
 };
@@ -97,8 +96,6 @@ use crate::{
 #[cfg(test)]
 mod tests;
 
-pub const APPROVAL_SESSIONS: SessionWindowSize = new_session_window_size!(6);
-
 const APPROVAL_CHECKING_TIMEOUT: Duration = Duration::from_secs(120);
 /// How long are we willing to wait for approval signatures?
 ///
@@ -118,7 +115,9 @@ const LOG_TARGET: &str = "parachain::approval-voting";
 #[derive(Debug, Clone)]
 pub struct Config {
 	/// The column family in the DB where approval-voting data is stored.
-	pub col_data: u32,
+	pub col_approval_data: u32,
+	/// The of the DB where rolling session info is stored.
+	pub col_session_data: u32,
 	/// The slot duration of the consensus algorithm, in milliseconds. Should be evenly
 	/// divisible by 500.
 	pub slot_duration_millis: u64,
@@ -358,7 +357,10 @@ impl ApprovalVotingSubsystem {
 			keystore,
 			slot_duration_millis: config.slot_duration_millis,
 			db,
-			db_config: DatabaseConfig { col_data: config.col_data },
+			db_config: DatabaseConfig {
+				col_approval_data: config.col_approval_data,
+				col_session_data: config.col_session_data,
+			},
 			mode: Mode::Syncing(sync_oracle),
 			metrics,
 		}
@@ -367,7 +369,10 @@ impl ApprovalVotingSubsystem {
 	/// Revert to the block corresponding to the specified `hash`.
 	/// The operation is not allowed for blocks older than the last finalized one.
 	pub fn revert_to(&self, hash: Hash) -> Result<(), SubsystemError> {
-		let config = approval_db::v1::Config { col_data: self.db_config.col_data };
+		let config = approval_db::v1::Config {
+			col_approval_data: self.db_config.col_approval_data,
+			col_session_data: self.db_config.col_session_data,
+		};
 		let mut backend = approval_db::v1::DbBackend::new(self.db.clone(), config);
 		let mut overlay = OverlayedBackend::new(&backend);
 
@@ -634,6 +639,9 @@ struct State {
 	slot_duration_millis: u64,
 	clock: Box<dyn Clock + Send + Sync>,
 	assignment_criteria: Box<dyn AssignmentCriteria + Send + Sync>,
+	// Require for `RollingSessionWindow`.
+	db_config: DatabaseConfig,
+	db: Arc<dyn Database>,
 }
 
 #[overseer::contextbounds(ApprovalVoting, prefix = self::overseer)]
@@ -655,8 +663,17 @@ impl State {
 		match session_window {
 			None => {
 				let sender = ctx.sender().clone();
-				self.session_window =
-					Some(RollingSessionWindow::new(sender, APPROVAL_SESSIONS, head).await?);
+				self.session_window = Some(
+					RollingSessionWindow::new(
+						sender,
+						head,
+						DatabaseParams {
+							db: self.db.clone(),
+							db_column: self.db_config.col_session_data,
+						},
+					)
+					.await?,
+				);
 				Ok(None)
 			},
 			Some(mut session_window) => {
@@ -751,7 +768,7 @@ async fn run<B, Context>(
 where
 	B: Backend,
 {
-	if let Err(err) = db_sanity_check(subsystem.db, subsystem.db_config) {
+	if let Err(err) = db_sanity_check(subsystem.db.clone(), subsystem.db_config.clone()) {
 		gum::warn!(target: LOG_TARGET, ?err, "Could not run approval vote DB sanity check");
 	}
 
@@ -761,6 +778,8 @@ where
 		slot_duration_millis: subsystem.slot_duration_millis,
 		clock,
 		assignment_criteria,
+		db_config: subsystem.db_config,
+		db: subsystem.db,
 	};
 
 	let mut wakeups = Wakeups::default();
diff --git a/node/core/approval-voting/src/tests.rs b/node/core/approval-voting/src/tests.rs
index d5c8d3c01da4..b9063c8ade25 100644
--- a/node/core/approval-voting/src/tests.rs
+++ b/node/core/approval-voting/src/tests.rs
@@ -14,6 +14,8 @@
 // You should have received a copy of the GNU General Public License
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
+use crate::tests::test_constants::TEST_CONFIG;
+
 use super::*;
 use polkadot_node_primitives::{
 	approval::{
@@ -111,9 +113,12 @@ fn make_sync_oracle(val: bool) -> (Box<dyn SyncOracle + Send>, TestSyncOracleHan
 pub mod test_constants {
 	use crate::approval_db::v1::Config as DatabaseConfig;
 	const DATA_COL: u32 = 0;
-	pub(crate) const NUM_COLUMNS: u32 = 1;
+	const SESSION_DATA_COL: u32 = 1;
+
+	pub(crate) const NUM_COLUMNS: u32 = 2;
 
-	pub(crate) const TEST_CONFIG: DatabaseConfig = DatabaseConfig { col_data: DATA_COL };
+	pub(crate) const TEST_CONFIG: DatabaseConfig =
+		DatabaseConfig { col_approval_data: DATA_COL, col_session_data: SESSION_DATA_COL };
 }
 
 struct MockSupportsParachains;
@@ -487,8 +492,9 @@ fn test_harness<T: Future<Output = VirtualOverseer>>(
 		context,
 		ApprovalVotingSubsystem::with_config(
 			Config {
-				col_data: test_constants::TEST_CONFIG.col_data,
+				col_approval_data: test_constants::TEST_CONFIG.col_approval_data,
 				slot_duration_millis: SLOT_DURATION_MILLIS,
+				col_session_data: TEST_CONFIG.col_session_data,
 			},
 			Arc::new(db),
 			Arc::new(keystore),
@@ -810,38 +816,38 @@ async fn import_block(
 		}
 	);
 
-	assert_matches!(
-		overseer_recv(overseer).await,
-		AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
-			s_tx,
-		)) => {
-			let _ = s_tx.send(Ok(number));
-		}
-	);
+	if !fork {
+		assert_matches!(
+			overseer_recv(overseer).await,
+			AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
+				s_tx,
+			)) => {
+				let _ = s_tx.send(Ok(number));
+			}
+		);
 
-	assert_matches!(
-		overseer_recv(overseer).await,
-		AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
-			block_number,
-			s_tx,
-		)) => {
-			assert_eq!(block_number, number);
-			let _ = s_tx.send(Ok(Some(hashes[number as usize].0)));
-		}
-	);
+		assert_matches!(
+			overseer_recv(overseer).await,
+			AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
+				block_number,
+				s_tx,
+			)) => {
+				assert_eq!(block_number, number);
+				let _ = s_tx.send(Ok(Some(hashes[number as usize].0)));
+			}
+		);
 
-	assert_matches!(
-		overseer_recv(overseer).await,
-		AllMessages::RuntimeApi(RuntimeApiMessage::Request(
-			h,
-			RuntimeApiRequest::SessionIndexForChild(s_tx),
-		)) => {
-			assert_eq!(h, hashes[number as usize].0);
-			let _ = s_tx.send(Ok(number.into()));
-		}
-	);
+		assert_matches!(
+			overseer_recv(overseer).await,
+			AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+				h,
+				RuntimeApiRequest::SessionIndexForChild(s_tx),
+			)) => {
+				assert_eq!(h, hashes[number as usize].0);
+				let _ = s_tx.send(Ok(number.into()));
+			}
+		);
 
-	if !fork {
 		assert_matches!(
 			overseer_recv(overseer).await,
 			AllMessages::RuntimeApi(
diff --git a/node/core/candidate-validation/Cargo.toml b/node/core/candidate-validation/Cargo.toml
index 8634cfe5a75e..105d7c1a21dc 100644
--- a/node/core/candidate-validation/Cargo.toml
+++ b/node/core/candidate-validation/Cargo.toml
@@ -7,6 +7,7 @@ edition = "2021"
 [dependencies]
 async-trait = "0.1.57"
 futures = "0.3.21"
+futures-timer = "3.0.2"
 gum = { package = "tracing-gum", path = "../../gum" }
 
 sp-maybe-compressed-blob = { package = "sp-maybe-compressed-blob", git = "https://github.com/paritytech/substrate", branch = "master" }
diff --git a/node/core/candidate-validation/src/lib.rs b/node/core/candidate-validation/src/lib.rs
index c3775ba1c453..a82a0feb78a0 100644
--- a/node/core/candidate-validation/src/lib.rs
+++ b/node/core/candidate-validation/src/lib.rs
@@ -60,6 +60,12 @@ mod tests;
 
 const LOG_TARGET: &'static str = "parachain::candidate-validation";
 
+/// The amount of time to wait before retrying after an AmbiguousWorkerDeath validation error.
+#[cfg(not(test))]
+const PVF_EXECUTION_RETRY_DELAY: Duration = Duration::from_secs(3);
+#[cfg(test)]
+const PVF_EXECUTION_RETRY_DELAY: Duration = Duration::from_millis(200);
+
 /// Configuration for the candidate validation subsystem
 #[derive(Clone)]
 pub struct Config {
@@ -490,7 +496,7 @@ where
 }
 
 async fn validate_candidate_exhaustive(
-	mut validation_backend: impl ValidationBackend,
+	mut validation_backend: impl ValidationBackend + Send,
 	persisted_validation_data: PersistedValidationData,
 	validation_code: ValidationCode,
 	candidate_receipt: CandidateReceipt,
@@ -551,7 +557,7 @@ async fn validate_candidate_exhaustive(
 	};
 
 	let result = validation_backend
-		.validate_candidate(raw_validation_code.to_vec(), timeout, params)
+		.validate_candidate_with_retry(raw_validation_code.to_vec(), timeout, params)
 		.await;
 
 	if let Err(ref error) = result {
@@ -604,45 +610,63 @@ async fn validate_candidate_exhaustive(
 #[async_trait]
 trait ValidationBackend {
 	async fn validate_candidate(
+		&mut self,
+		pvf: Pvf,
+		timeout: Duration,
+		encoded_params: Vec<u8>,
+	) -> Result<WasmValidationResult, ValidationError>;
+
+	async fn validate_candidate_with_retry(
 		&mut self,
 		raw_validation_code: Vec<u8>,
 		timeout: Duration,
 		params: ValidationParams,
-	) -> Result<WasmValidationResult, ValidationError>;
+	) -> Result<WasmValidationResult, ValidationError> {
+		// Construct the PVF a single time, since it is an expensive operation. Cloning it is cheap.
+		let pvf = Pvf::from_code(raw_validation_code);
+
+		let validation_result =
+			self.validate_candidate(pvf.clone(), timeout, params.encode()).await;
+
+		// If we get an AmbiguousWorkerDeath error, retry once after a brief delay, on the
+		// assumption that the conditions that caused this error may have been transient.
+		if let Err(ValidationError::InvalidCandidate(WasmInvalidCandidate::AmbiguousWorkerDeath)) =
+			validation_result
+		{
+			// Wait a brief delay before retrying.
+			futures_timer::Delay::new(PVF_EXECUTION_RETRY_DELAY).await;
+			// Encode the params again when re-trying. We expect the retry case to be relatively
+			// rare, and we want to avoid unconditionally cloning data.
+			self.validate_candidate(pvf, timeout, params.encode()).await
+		} else {
+			validation_result
+		}
+	}
 
 	async fn precheck_pvf(&mut self, pvf: Pvf) -> Result<(), PrepareError>;
 }
 
 #[async_trait]
 impl ValidationBackend for ValidationHost {
+	/// Tries executing a PVF a single time (no retries).
 	async fn validate_candidate(
 		&mut self,
-		raw_validation_code: Vec<u8>,
+		pvf: Pvf,
 		timeout: Duration,
-		params: ValidationParams,
+		encoded_params: Vec<u8>,
 	) -> Result<WasmValidationResult, ValidationError> {
+		let priority = polkadot_node_core_pvf::Priority::Normal;
+
 		let (tx, rx) = oneshot::channel();
-		if let Err(err) = self
-			.execute_pvf(
-				Pvf::from_code(raw_validation_code),
-				timeout,
-				params.encode(),
-				polkadot_node_core_pvf::Priority::Normal,
-				tx,
-			)
-			.await
-		{
+		if let Err(err) = self.execute_pvf(pvf, timeout, encoded_params, priority, tx).await {
 			return Err(ValidationError::InternalError(format!(
 				"cannot send pvf to the validation host: {:?}",
 				err
 			)))
 		}
 
-		let validation_result = rx
-			.await
-			.map_err(|_| ValidationError::InternalError("validation was cancelled".into()))?;
-
-		validation_result
+		rx.await
+			.map_err(|_| ValidationError::InternalError("validation was cancelled".into()))?
 	}
 
 	async fn precheck_pvf(&mut self, pvf: Pvf) -> Result<(), PrepareError> {
diff --git a/node/core/candidate-validation/src/tests.rs b/node/core/candidate-validation/src/tests.rs
index ecac13d1440d..cf467cd5c057 100644
--- a/node/core/candidate-validation/src/tests.rs
+++ b/node/core/candidate-validation/src/tests.rs
@@ -345,12 +345,19 @@ fn check_does_not_match() {
 }
 
 struct MockValidateCandidateBackend {
-	result: Result<WasmValidationResult, ValidationError>,
+	result_list: Vec<Result<WasmValidationResult, ValidationError>>,
+	num_times_called: usize,
 }
 
 impl MockValidateCandidateBackend {
 	fn with_hardcoded_result(result: Result<WasmValidationResult, ValidationError>) -> Self {
-		Self { result }
+		Self { result_list: vec![result], num_times_called: 0 }
+	}
+
+	fn with_hardcoded_result_list(
+		result_list: Vec<Result<WasmValidationResult, ValidationError>>,
+	) -> Self {
+		Self { result_list, num_times_called: 0 }
 	}
 }
 
@@ -358,11 +365,16 @@ impl MockValidateCandidateBackend {
 impl ValidationBackend for MockValidateCandidateBackend {
 	async fn validate_candidate(
 		&mut self,
-		_raw_validation_code: Vec<u8>,
+		_pvf: Pvf,
 		_timeout: Duration,
-		_params: ValidationParams,
+		_encoded_params: Vec<u8>,
 	) -> Result<WasmValidationResult, ValidationError> {
-		self.result.clone()
+		// This is expected to panic if called more times than expected, indicating an error in the
+		// test.
+		let result = self.result_list[self.num_times_called].clone();
+		self.num_times_called += 1;
+
+		result
 	}
 
 	async fn precheck_pvf(&mut self, _pvf: Pvf) -> Result<(), PrepareError> {
@@ -468,7 +480,7 @@ fn candidate_validation_bad_return_is_invalid() {
 
 	let v = executor::block_on(validate_candidate_exhaustive(
 		MockValidateCandidateBackend::with_hardcoded_result(Err(
-			ValidationError::InvalidCandidate(WasmInvalidCandidate::AmbiguousWorkerDeath),
+			ValidationError::InvalidCandidate(WasmInvalidCandidate::HardTimeout),
 		)),
 		validation_data,
 		validation_code,
@@ -479,6 +491,122 @@ fn candidate_validation_bad_return_is_invalid() {
 	))
 	.unwrap();
 
+	assert_matches!(v, ValidationResult::Invalid(InvalidCandidate::Timeout));
+}
+
+#[test]
+fn candidate_validation_one_ambiguous_error_is_valid() {
+	let validation_data = PersistedValidationData { max_pov_size: 1024, ..Default::default() };
+
+	let pov = PoV { block_data: BlockData(vec![1; 32]) };
+	let head_data = HeadData(vec![1, 1, 1]);
+	let validation_code = ValidationCode(vec![2; 16]);
+
+	let descriptor = make_valid_candidate_descriptor(
+		ParaId::from(1_u32),
+		dummy_hash(),
+		validation_data.hash(),
+		pov.hash(),
+		validation_code.hash(),
+		head_data.hash(),
+		dummy_hash(),
+		Sr25519Keyring::Alice,
+	);
+
+	let check = perform_basic_checks(
+		&descriptor,
+		validation_data.max_pov_size,
+		&pov,
+		&validation_code.hash(),
+	);
+	assert!(check.is_ok());
+
+	let validation_result = WasmValidationResult {
+		head_data,
+		new_validation_code: Some(vec![2, 2, 2].into()),
+		upward_messages: Vec::new(),
+		horizontal_messages: Vec::new(),
+		processed_downward_messages: 0,
+		hrmp_watermark: 0,
+	};
+
+	let commitments = CandidateCommitments {
+		head_data: validation_result.head_data.clone(),
+		upward_messages: validation_result.upward_messages.clone(),
+		horizontal_messages: validation_result.horizontal_messages.clone(),
+		new_validation_code: validation_result.new_validation_code.clone(),
+		processed_downward_messages: validation_result.processed_downward_messages,
+		hrmp_watermark: validation_result.hrmp_watermark,
+	};
+
+	let candidate_receipt = CandidateReceipt { descriptor, commitments_hash: commitments.hash() };
+
+	let v = executor::block_on(validate_candidate_exhaustive(
+		MockValidateCandidateBackend::with_hardcoded_result_list(vec![
+			Err(ValidationError::InvalidCandidate(WasmInvalidCandidate::AmbiguousWorkerDeath)),
+			Ok(validation_result),
+		]),
+		validation_data.clone(),
+		validation_code,
+		candidate_receipt,
+		Arc::new(pov),
+		Duration::from_secs(0),
+		&Default::default(),
+	))
+	.unwrap();
+
+	assert_matches!(v, ValidationResult::Valid(outputs, used_validation_data) => {
+		assert_eq!(outputs.head_data, HeadData(vec![1, 1, 1]));
+		assert_eq!(outputs.upward_messages, Vec::<UpwardMessage>::new());
+		assert_eq!(outputs.horizontal_messages, Vec::new());
+		assert_eq!(outputs.new_validation_code, Some(vec![2, 2, 2].into()));
+		assert_eq!(outputs.hrmp_watermark, 0);
+		assert_eq!(used_validation_data, validation_data);
+	});
+}
+
+#[test]
+fn candidate_validation_multiple_ambiguous_errors_is_invalid() {
+	let validation_data = PersistedValidationData { max_pov_size: 1024, ..Default::default() };
+
+	let pov = PoV { block_data: BlockData(vec![1; 32]) };
+	let validation_code = ValidationCode(vec![2; 16]);
+
+	let descriptor = make_valid_candidate_descriptor(
+		ParaId::from(1_u32),
+		dummy_hash(),
+		validation_data.hash(),
+		pov.hash(),
+		validation_code.hash(),
+		dummy_hash(),
+		dummy_hash(),
+		Sr25519Keyring::Alice,
+	);
+
+	let check = perform_basic_checks(
+		&descriptor,
+		validation_data.max_pov_size,
+		&pov,
+		&validation_code.hash(),
+	);
+	assert!(check.is_ok());
+
+	let candidate_receipt = CandidateReceipt { descriptor, commitments_hash: Hash::zero() };
+
+	let v = executor::block_on(validate_candidate_exhaustive(
+		MockValidateCandidateBackend::with_hardcoded_result_list(vec![
+			Err(ValidationError::InvalidCandidate(WasmInvalidCandidate::AmbiguousWorkerDeath)),
+			Err(ValidationError::InvalidCandidate(WasmInvalidCandidate::AmbiguousWorkerDeath)),
+		]),
+		validation_data,
+		validation_code,
+		candidate_receipt,
+		Arc::new(pov),
+		Duration::from_secs(0),
+		&Default::default(),
+	))
+	.unwrap();
+
 	assert_matches!(v, ValidationResult::Invalid(InvalidCandidate::ExecutionError(_)));
 }
 
@@ -779,9 +907,9 @@ impl MockPreCheckBackend {
 impl ValidationBackend for MockPreCheckBackend {
 	async fn validate_candidate(
 		&mut self,
-		_raw_validation_code: Vec<u8>,
+		_pvf: Pvf,
 		_timeout: Duration,
-		_params: ValidationParams,
+		_encoded_params: Vec<u8>,
 	) -> Result<WasmValidationResult, ValidationError> {
 		unreachable!()
 	}
diff --git a/node/core/dispute-coordinator/src/db/v1.rs b/node/core/dispute-coordinator/src/db/v1.rs
index 2c643d341de2..bb1456a59745 100644
--- a/node/core/dispute-coordinator/src/db/v1.rs
+++ b/node/core/dispute-coordinator/src/db/v1.rs
@@ -99,10 +99,10 @@ impl DbBackend {
 			encoded = ?candidate_votes_session_prefix(index),
 			"Cleaning votes for session index"
 			);
-			tx.delete_prefix(self.config.col_data, &candidate_votes_session_prefix(index));
+			tx.delete_prefix(self.config.col_dispute_data, &candidate_votes_session_prefix(index));
 		}
 		// New watermark:
-		tx.put_vec(self.config.col_data, CLEANED_VOTES_WATERMARK_KEY, clean_until.encode());
+		tx.put_vec(self.config.col_dispute_data, CLEANED_VOTES_WATERMARK_KEY, clean_until.encode());
 		Ok(())
 	}
 }
@@ -148,21 +148,32 @@ impl Backend for DbBackend {
 					self.add_vote_cleanup_tx(&mut tx, session)?;
 
 					// Actually write the earliest session.
-					tx.put_vec(self.config.col_data, EARLIEST_SESSION_KEY, session.encode());
+					tx.put_vec(
+						self.config.col_dispute_data,
+						EARLIEST_SESSION_KEY,
+						session.encode(),
+					);
 				},
 				BackendWriteOp::WriteRecentDisputes(recent_disputes) => {
-					tx.put_vec(self.config.col_data, RECENT_DISPUTES_KEY, recent_disputes.encode());
+					tx.put_vec(
+						self.config.col_dispute_data,
+						RECENT_DISPUTES_KEY,
+						recent_disputes.encode(),
+					);
 				},
 				BackendWriteOp::WriteCandidateVotes(session, candidate_hash, votes) => {
 					gum::trace!(target: LOG_TARGET, ?session, "Writing candidate votes");
 					tx.put_vec(
-						self.config.col_data,
+						self.config.col_dispute_data,
 						&candidate_votes_key(session, &candidate_hash),
 						votes.encode(),
 					);
 				},
 				BackendWriteOp::DeleteCandidateVotes(session, candidate_hash) => {
-					tx.delete(self.config.col_data, &candidate_votes_key(session, &candidate_hash));
+					tx.delete(
+						self.config.col_dispute_data,
+						&candidate_votes_key(session, &candidate_hash),
+					);
 				},
 			}
 		}
@@ -195,7 +206,9 @@ fn candidate_votes_session_prefix(session: SessionIndex) -> [u8; 15 + 4] {
 #[derive(Debug, Clone)]
 pub struct ColumnConfiguration {
 	/// The column in the key-value DB where data is stored.
-	pub col_data: u32,
+	pub col_dispute_data: u32,
+	/// The column in the key-value DB where session data is stored.
+	pub col_session_data: u32,
 }
 
 /// Tracked votes on candidates, for the purposes of dispute resolution.
@@ -257,8 +270,12 @@ impl From<Error> for crate::error::Error {
 /// Result alias for DB errors.
 pub type Result<T> = std::result::Result<T, Error>;
 
-fn load_decode<D: Decode>(db: &dyn Database, col_data: u32, key: &[u8]) -> Result<Option<D>> {
-	match db.get(col_data, key)? {
+fn load_decode<D: Decode>(
+	db: &dyn Database,
+	col_dispute_data: u32,
+	key: &[u8],
+) -> Result<Option<D>> {
+	match db.get(col_dispute_data, key)? {
 		None => Ok(None),
 		Some(raw) => D::decode(&mut &raw[..]).map(Some).map_err(Into::into),
 	}
@@ -271,7 +288,7 @@ pub(crate) fn load_candidate_votes(
 	session: SessionIndex,
 	candidate_hash: &CandidateHash,
 ) -> SubsystemResult<Option<CandidateVotes>> {
-	load_decode(db, config.col_data, &candidate_votes_key(session, candidate_hash))
+	load_decode(db, config.col_dispute_data, &candidate_votes_key(session, candidate_hash))
 		.map_err(|e| SubsystemError::with_origin("dispute-coordinator", e))
 }
 
@@ -280,7 +297,7 @@ pub(crate) fn load_earliest_session(
 	db: &dyn Database,
 	config: &ColumnConfiguration,
 ) -> SubsystemResult<Option<SessionIndex>> {
-	load_decode(db, config.col_data, EARLIEST_SESSION_KEY)
+	load_decode(db, config.col_dispute_data, EARLIEST_SESSION_KEY)
 		.map_err(|e| SubsystemError::with_origin("dispute-coordinator", e))
 }
 
@@ -289,7 +306,7 @@ pub(crate) fn load_recent_disputes(
 	db: &dyn Database,
 	config: &ColumnConfiguration,
 ) -> SubsystemResult<Option<RecentDisputes>> {
-	load_decode(db, config.col_data, RECENT_DISPUTES_KEY)
+	load_decode(db, config.col_dispute_data, RECENT_DISPUTES_KEY)
 		.map_err(|e| SubsystemError::with_origin("dispute-coordinator", e))
 }
 
@@ -347,7 +364,7 @@ fn load_cleaned_votes_watermark(
 	db: &dyn Database,
 	config: &ColumnConfiguration,
 ) -> FatalResult<Option<SessionIndex>> {
-	load_decode(db, config.col_data, CLEANED_VOTES_WATERMARK_KEY)
+	load_decode(db, config.col_dispute_data, CLEANED_VOTES_WATERMARK_KEY)
 		.map_err(|e| FatalError::DbReadFailed(e))
 }
 
@@ -362,7 +379,7 @@ mod tests {
 		let db = kvdb_memorydb::create(1);
 		let db = polkadot_node_subsystem_util::database::kvdb_impl::DbAdapter::new(db, &[0]);
 		let store = Arc::new(db);
-		let config = ColumnConfiguration { col_data: 0 };
+		let config = ColumnConfiguration { col_dispute_data: 0, col_session_data: 1 };
 		DbBackend::new(store, config, Metrics::default())
 	}
 
diff --git a/node/core/dispute-coordinator/src/lib.rs b/node/core/dispute-coordinator/src/lib.rs
index 6289eb2f11a2..03abd8f59d60 100644
--- a/node/core/dispute-coordinator/src/lib.rs
+++ b/node/core/dispute-coordinator/src/lib.rs
@@ -35,7 +35,8 @@ use polkadot_node_subsystem::{
 	overseer, ActivatedLeaf, FromOrchestra, OverseerSignal, SpawnedSubsystem, SubsystemError,
 };
 use polkadot_node_subsystem_util::{
-	database::Database, rolling_session_window::RollingSessionWindow,
+	database::Database,
+	rolling_session_window::{DatabaseParams, RollingSessionWindow},
 };
 use polkadot_primitives::v2::{ScrapedOnChainVotes, ValidatorIndex, ValidatorPair};
 
@@ -117,12 +118,17 @@ pub struct DisputeCoordinatorSubsystem {
 #[derive(Debug, Clone, Copy)]
 pub struct Config {
 	/// The data column in the store to use for dispute data.
-	pub col_data: u32,
+	pub col_dispute_data: u32,
+	/// The data column in the store to use for session data.
+	pub col_session_data: u32,
 }
 
 impl Config {
 	fn column_config(&self) -> db::v1::ColumnConfiguration {
-		db::v1::ColumnConfiguration { col_data: self.col_data }
+		db::v1::ColumnConfiguration {
+			col_dispute_data: self.col_dispute_data,
+			col_session_data: self.col_session_data,
+		}
 	}
 }
 
@@ -199,17 +205,21 @@ impl DisputeCoordinatorSubsystem {
 		B: Backend + 'static,
 	{
 		loop {
-			let (first_leaf, rolling_session_window) = match get_rolling_session_window(ctx).await {
-				Ok(Some(update)) => update,
-				Ok(None) => {
-					gum::info!(target: LOG_TARGET, "received `Conclude` signal, exiting");
-					return Ok(None)
-				},
-				Err(e) => {
-					e.split()?.log();
-					continue
-				},
-			};
+			let db_params =
+				DatabaseParams { db: self.store.clone(), db_column: self.config.col_session_data };
+
+			let (first_leaf, rolling_session_window) =
+				match get_rolling_session_window(ctx, db_params).await {
+					Ok(Some(update)) => update,
+					Ok(None) => {
+						gum::info!(target: LOG_TARGET, "received `Conclude` signal, exiting");
+						return Ok(None)
+					},
+					Err(e) => {
+						e.split()?.log();
+						continue
+					},
+				};
 
 			let mut overlay_db = OverlayedBackend::new(&mut backend);
 			let (participations, votes, spam_slots, ordering_provider) = match self
@@ -352,12 +362,13 @@ impl DisputeCoordinatorSubsystem {
 #[overseer::contextbounds(DisputeCoordinator, prefix = self::overseer)]
 async fn get_rolling_session_window<Context>(
 	ctx: &mut Context,
+	db_params: DatabaseParams,
 ) -> Result<Option<(ActivatedLeaf, RollingSessionWindow)>> {
 	if let Some(leaf) = { wait_for_first_leaf(ctx) }.await? {
 		let sender = ctx.sender().clone();
 		Ok(Some((
 			leaf.clone(),
-			RollingSessionWindow::new(sender, DISPUTE_WINDOW, leaf.hash)
+			RollingSessionWindow::new(sender, leaf.hash, db_params)
 				.await
 				.map_err(JfyiError::RollingSessionWindow)?,
 		)))
diff --git a/node/core/dispute-coordinator/src/tests.rs b/node/core/dispute-coordinator/src/tests.rs
index c6fe328d9537..a1ad315d2ea0 100644
--- a/node/core/dispute-coordinator/src/tests.rs
+++ b/node/core/dispute-coordinator/src/tests.rs
@@ -176,7 +176,7 @@ impl Default for TestState {
 		let db = kvdb_memorydb::create(1);
 		let db = polkadot_node_subsystem_util::database::kvdb_impl::DbAdapter::new(db, &[]);
 		let db = Arc::new(db);
-		let config = Config { col_data: 0 };
+		let config = Config { col_dispute_data: 0, col_session_data: 1 };
 
 		let genesis_header = Header {
 			parent_hash: Hash::zero(),
@@ -251,6 +251,7 @@ impl TestState {
 		session: SessionIndex,
 	) {
 		// Order of messages is not fixed (different on initializing):
+		#[derive(Debug)]
 		struct FinishedSteps {
 			got_session_information: bool,
 			got_scraping_information: bool,
@@ -268,7 +269,8 @@ impl TestState {
 		let mut finished_steps = FinishedSteps::new();
 
 		while !finished_steps.is_done() {
-			match overseer_recv(virtual_overseer).await {
+			let recv = overseer_recv(virtual_overseer).await;
+			match recv {
 				AllMessages::RuntimeApi(RuntimeApiMessage::Request(
 					h,
 					RuntimeApiRequest::SessionIndexForChild(tx),
@@ -282,36 +284,38 @@ impl TestState {
 					let _ = tx.send(Ok(session));
 
 					// Queries for fetching earliest unfinalized block session. See `RollingSessionWindow`.
-					assert_matches!(
-						overseer_recv(virtual_overseer).await,
-						AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
-							s_tx,
-						)) => {
-							let _ = s_tx.send(Ok(block_number));
-						}
-					);
+					if self.known_session.is_none() {
+						assert_matches!(
+							overseer_recv(virtual_overseer).await,
+							AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
+								s_tx,
+							)) => {
+								let _ = s_tx.send(Ok(block_number));
+							}
+						);
 
-					assert_matches!(
-						overseer_recv(virtual_overseer).await,
-						AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
-							number,
-							s_tx,
-						)) => {
-							assert_eq!(block_number, number);
-							let _ = s_tx.send(Ok(Some(block_hash)));
-						}
-					);
+						assert_matches!(
+							overseer_recv(virtual_overseer).await,
+							AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
+								number,
+								s_tx,
+							)) => {
+								assert_eq!(block_number, number);
+								let _ = s_tx.send(Ok(Some(block_hash)));
+							}
+						);
 
-					assert_matches!(
-						overseer_recv(virtual_overseer).await,
-						AllMessages::RuntimeApi(RuntimeApiMessage::Request(
-							h,
-							RuntimeApiRequest::SessionIndexForChild(s_tx),
-						)) => {
-							assert_eq!(h, block_hash);
-							let _ = s_tx.send(Ok(session));
-						}
-					);
+						assert_matches!(
+							overseer_recv(virtual_overseer).await,
+							AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+								h,
+								RuntimeApiRequest::SessionIndexForChild(s_tx),
+							)) => {
+								assert_eq!(h, block_hash);
+								let _ = s_tx.send(Ok(session));
+							}
+						);
+					}
 
 					// No queries, if subsystem knows about this session already.
 					if self.known_session == Some(session) {
@@ -754,6 +758,7 @@ fn approval_vote_import_works() {
 			let approval_votes = [(ValidatorIndex(4), approval_vote.into_validator_signature())]
 				.into_iter()
 				.collect();
+
 			handle_approval_vote_request(&mut virtual_overseer, &candidate_hash1, approval_votes)
 				.await;
 
@@ -2255,6 +2260,7 @@ fn resume_dispute_with_local_statement() {
 					},
 				})
 				.await;
+
 			handle_approval_vote_request(&mut virtual_overseer, &candidate_hash, HashMap::new())
 				.await;
 
@@ -2469,6 +2475,7 @@ fn resume_dispute_with_local_statement_without_local_key() {
 			test_state
 		})
 	});
+
 	// No keys:
 	test_state.subsystem_keystore =
 		make_keystore(vec![Sr25519Keyring::Two.to_seed()].into_iter()).into();
diff --git a/node/core/pvf/src/artifacts.rs b/node/core/pvf/src/artifacts.rs
index 32f487cfc062..038d8e803299 100644
--- a/node/core/pvf/src/artifacts.rs
+++ b/node/core/pvf/src/artifacts.rs
@@ -103,10 +103,22 @@ pub enum ArtifactState {
 		last_time_needed: SystemTime,
 	},
 	/// A task to prepare this artifact is scheduled.
-	Preparing { waiting_for_response: Vec<PrepareResultSender> },
+	Preparing {
+		/// List of result senders that are waiting for a response.
+		waiting_for_response: Vec<PrepareResultSender>,
+		/// The number of times this artifact has failed to prepare.
+		num_failures: u32,
+	},
 	/// The code couldn't be compiled due to an error. Such artifacts
 	/// never reach the executor and stay in the host's memory.
-	FailedToProcess(PrepareError),
+	FailedToProcess {
+		/// Keep track of the last time that processing this artifact failed.
+		last_time_failed: SystemTime,
+		/// The number of times this artifact has failed to prepare.
+		num_failures: u32,
+		/// The last error encountered for preparation.
+		error: PrepareError,
+	},
 }
 
 /// A container of all known artifact ids and their states.
@@ -150,7 +162,7 @@ impl Artifacts {
 		// See the precondition.
 		always!(self
 			.artifacts
-			.insert(artifact_id, ArtifactState::Preparing { waiting_for_response })
+			.insert(artifact_id, ArtifactState::Preparing { waiting_for_response, num_failures: 0 })
 			.is_none());
 	}
 
diff --git a/node/core/pvf/src/execute/queue.rs b/node/core/pvf/src/execute/queue.rs
index 9b240e02df17..b4c6a66b7719 100644
--- a/node/core/pvf/src/execute/queue.rs
+++ b/node/core/pvf/src/execute/queue.rs
@@ -252,8 +252,8 @@ fn handle_job_finish(
 		"execute worker concluded",
 	);
 
-	// First we send the result. It may fail due the other end of the channel being dropped, that's
-	// legitimate and we don't treat that as an error.
+	// First we send the result. It may fail due to the other end of the channel being dropped,
+	// that's legitimate and we don't treat that as an error.
 	let _ = result_tx.send(result);
 
 	// Then, we should deal with the worker:
@@ -305,7 +305,7 @@ async fn spawn_worker_task(program_path: PathBuf, spawn_timeout: Duration) -> Qu
 			Err(err) => {
 				gum::warn!(target: LOG_TARGET, "failed to spawn an execute worker: {:?}", err);
 
-				// Assume that the failure intermittent and retry after a delay.
+				// Assume that the failure is intermittent and retry after a delay.
 				Delay::new(Duration::from_secs(3)).await;
 			},
 		}
diff --git a/node/core/pvf/src/host.rs b/node/core/pvf/src/host.rs
index 69f2e07b56cc..5c29072da1c3 100644
--- a/node/core/pvf/src/host.rs
+++ b/node/core/pvf/src/host.rs
@@ -22,6 +22,7 @@
 
 use crate::{
 	artifacts::{ArtifactId, ArtifactPathId, ArtifactState, Artifacts},
+	error::PrepareError,
 	execute,
 	metrics::Metrics,
 	prepare, PrepareResult, Priority, Pvf, ValidationError, LOG_TARGET,
@@ -49,6 +50,16 @@ pub const PRECHECK_PREPARATION_TIMEOUT: Duration = Duration::from_secs(60);
 // NOTE: If you change this make sure to fix the buckets of `pvf_preparation_time` metric.
 pub const LENIENT_PREPARATION_TIMEOUT: Duration = Duration::from_secs(360);
 
+/// The time period after which a failed preparation artifact is considered ready to be retried.
+/// Note that we will only retry if another request comes in after this cooldown has passed.
+#[cfg(not(test))]
+pub const PREPARE_FAILURE_COOLDOWN: Duration = Duration::from_secs(15 * 60);
+#[cfg(test)]
+pub const PREPARE_FAILURE_COOLDOWN: Duration = Duration::from_millis(200);
+
+/// The amount of times we will retry failed prepare jobs.
+pub const NUM_PREPARE_RETRIES: u32 = 5;
+
 /// An alias to not spell the type for the oneshot sender for the PVF execution result.
 pub(crate) type ResultSender = oneshot::Sender<Result<ValidationResult, ValidationError>>;
 
@@ -97,7 +108,13 @@ impl ValidationHost {
 		result_tx: ResultSender,
 	) -> Result<(), String> {
 		self.to_host_tx
-			.send(ToHost::ExecutePvf { pvf, execution_timeout, params, priority, result_tx })
+			.send(ToHost::ExecutePvf(ExecutePvfInputs {
+				pvf,
+				execution_timeout,
+				params,
+				priority,
+				result_tx,
+			}))
 			.await
 			.map_err(|_| "the inner loop hung up".to_string())
 	}
@@ -117,20 +134,17 @@ impl ValidationHost {
 }
 
 enum ToHost {
-	PrecheckPvf {
-		pvf: Pvf,
-		result_tx: PrepareResultSender,
-	},
-	ExecutePvf {
-		pvf: Pvf,
-		execution_timeout: Duration,
-		params: Vec<u8>,
-		priority: Priority,
-		result_tx: ResultSender,
-	},
-	HeadsUp {
-		active_pvfs: Vec<Pvf>,
-	},
+	PrecheckPvf { pvf: Pvf, result_tx: PrepareResultSender },
+	ExecutePvf(ExecutePvfInputs),
+	HeadsUp { active_pvfs: Vec<Pvf> },
+}
+
+struct ExecutePvfInputs {
+	pvf: Pvf,
+	execution_timeout: Duration,
+	params: Vec<u8>,
+	priority: Priority,
+	result_tx: ResultSender,
 }
 
 /// Configuration for the validation host.
@@ -361,6 +375,8 @@ async fn run(
 					Some(to_host) => to_host,
 				};
 
+				// If the artifact failed before, it could be re-scheduled for preparation here if
+				// the preparation failure cooldown has elapsed.
 				break_if_fatal!(handle_to_host(
 					&cache_path,
 					&mut artifacts,
@@ -377,9 +393,9 @@ async fn run(
 				// Note that preparation always succeeds.
 				//
 				// That's because the error conditions are written into the artifact and will be
-				// reported at the time of the  execution. It potentially, but not necessarily,
-				// can be scheduled as a result of this function call, in case there are pending
-				// executions.
+				// reported at the time of the execution. It potentially, but not necessarily, can
+				// be scheduled for execution as a result of this function call, in case there are
+				// pending executions.
 				//
 				// We could be eager in terms of reporting and plumb the result from the preparation
 				// worker but we don't for the sake of simplicity.
@@ -407,24 +423,19 @@ async fn handle_to_host(
 		ToHost::PrecheckPvf { pvf, result_tx } => {
 			handle_precheck_pvf(artifacts, prepare_queue, pvf, result_tx).await?;
 		},
-		ToHost::ExecutePvf { pvf, execution_timeout, params, priority, result_tx } => {
+		ToHost::ExecutePvf(inputs) => {
 			handle_execute_pvf(
 				cache_path,
 				artifacts,
 				prepare_queue,
 				execute_queue,
 				awaiting_prepare,
-				pvf,
-				execution_timeout,
-				params,
-				priority,
-				result_tx,
+				inputs,
 			)
 			.await?;
 		},
-		ToHost::HeadsUp { active_pvfs } => {
-			handle_heads_up(artifacts, prepare_queue, active_pvfs).await?;
-		},
+		ToHost::HeadsUp { active_pvfs } =>
+			handle_heads_up(artifacts, prepare_queue, active_pvfs).await?,
 	}
 
 	Ok(())
@@ -432,8 +443,9 @@ async fn handle_to_host(
 
 /// Handles PVF prechecking requests.
 ///
-/// This tries to prepare the PVF by compiling the WASM blob within a given timeout
-/// ([`PRECHECK_PREPARATION_TIMEOUT`]).
+/// This tries to prepare the PVF by compiling the WASM blob within a given timeout ([`PRECHECK_COMPILATION_TIMEOUT`]).
+///
+/// If the prepare job failed previously, we may retry it under certain conditions.
 async fn handle_precheck_pvf(
 	artifacts: &mut Artifacts,
 	prepare_queue: &mut mpsc::Sender<prepare::ToQueue>,
@@ -448,10 +460,12 @@ async fn handle_precheck_pvf(
 				*last_time_needed = SystemTime::now();
 				let _ = result_sender.send(Ok(()));
 			},
-			ArtifactState::Preparing { waiting_for_response } =>
+			ArtifactState::Preparing { waiting_for_response, num_failures: _ } =>
 				waiting_for_response.push(result_sender),
-			ArtifactState::FailedToProcess(result) => {
-				let _ = result_sender.send(PrepareResult::Err(result.clone()));
+			ArtifactState::FailedToProcess { error, .. } => {
+				// Do not retry failed preparation if another pre-check request comes in. We do not retry pre-checking,
+				// anyway.
+				let _ = result_sender.send(PrepareResult::Err(error.clone()));
 			},
 		}
 	} else {
@@ -471,22 +485,22 @@ async fn handle_precheck_pvf(
 
 /// Handles PVF execution.
 ///
-/// This will first try to prepare the PVF, if a prepared artifact does not already exist. If there
-/// is already a preparation job, we coalesce the two preparation jobs. When preparing for
-/// execution, we use a more lenient timeout ([`LENIENT_PREPARATION_TIMEOUT`]) than when
-/// prechecking.
+/// This will try to prepare the PVF, if a prepared artifact does not already exist. If there is already a
+/// preparation job, we coalesce the two preparation jobs.
+///
+/// If the prepare job failed previously, we may retry it under certain conditions.
+///
+/// When preparing for execution, we use a more lenient timeout ([`EXECUTE_COMPILATION_TIMEOUT`])
+/// than when prechecking.
 async fn handle_execute_pvf(
 	cache_path: &Path,
 	artifacts: &mut Artifacts,
 	prepare_queue: &mut mpsc::Sender<prepare::ToQueue>,
 	execute_queue: &mut mpsc::Sender<execute::ToQueue>,
 	awaiting_prepare: &mut AwaitingPrepare,
-	pvf: Pvf,
-	execution_timeout: Duration,
-	params: Vec<u8>,
-	priority: Priority,
-	result_tx: ResultSender,
+	inputs: ExecutePvfInputs,
 ) -> Result<(), Fatal> {
+	let ExecutePvfInputs { pvf, execution_timeout, params, priority, result_tx } = inputs;
 	let artifact_id = pvf.as_artifact_id();
 
 	if let Some(state) = artifacts.artifact_state_mut(&artifact_id) {
@@ -494,6 +508,7 @@ async fn handle_execute_pvf(
 			ArtifactState::Prepared { last_time_needed } => {
 				*last_time_needed = SystemTime::now();
 
+				// This artifact has already been prepared, send it to the execute queue.
 				send_execute(
 					execute_queue,
 					execute::ToQueue::Enqueue {
@@ -505,11 +520,29 @@ async fn handle_execute_pvf(
 				)
 				.await?;
 			},
-			ArtifactState::Preparing { waiting_for_response: _ } => {
+			ArtifactState::Preparing { .. } => {
 				awaiting_prepare.add(artifact_id, execution_timeout, params, result_tx);
 			},
-			ArtifactState::FailedToProcess(error) => {
-				let _ = result_tx.send(Err(ValidationError::from(error.clone())));
+			ArtifactState::FailedToProcess { last_time_failed, num_failures, error } => {
+				if can_retry_prepare_after_failure(*last_time_failed, *num_failures, error) {
+					// If we are allowed to retry the failed prepare job, change the state to
+					// Preparing and re-queue this job.
+					*state = ArtifactState::Preparing {
+						waiting_for_response: Vec::new(),
+						num_failures: *num_failures,
+					};
+					send_prepare(
+						prepare_queue,
+						prepare::ToQueue::Enqueue {
+							priority,
+							pvf,
+							preparation_timeout: LENIENT_PREPARATION_TIMEOUT,
+						},
+					)
+					.await?;
+				} else {
+					let _ = result_tx.send(Err(ValidationError::from(error.clone())));
+				}
 			},
 		}
 	} else {
@@ -526,6 +559,7 @@ async fn handle_execute_pvf(
 		)
 		.await?;
 
+		// Add an execution request that will wait to run after this prepare job has finished.
 		awaiting_prepare.add(artifact_id, execution_timeout, params, result_tx);
 	}
 
@@ -546,10 +580,28 @@ async fn handle_heads_up(
 				ArtifactState::Prepared { last_time_needed, .. } => {
 					*last_time_needed = now;
 				},
-				ArtifactState::Preparing { waiting_for_response: _ } => {
+				ArtifactState::Preparing { .. } => {
 					// The artifact is already being prepared, so we don't need to do anything.
 				},
-				ArtifactState::FailedToProcess(_) => {},
+				ArtifactState::FailedToProcess { last_time_failed, num_failures, error } => {
+					if can_retry_prepare_after_failure(*last_time_failed, *num_failures, error) {
+						// If we are allowed to retry the failed prepare job, change the state to
+						// Preparing and re-queue this job.
+						*state = ArtifactState::Preparing {
+							waiting_for_response: vec![],
+							num_failures: *num_failures,
+						};
+						send_prepare(
+							prepare_queue,
+							prepare::ToQueue::Enqueue {
+								priority: Priority::Normal,
+								pvf: active_pvf,
+								preparation_timeout: LENIENT_PREPARATION_TIMEOUT,
+							},
+						)
+						.await?;
+					}
+				},
 			}
 		} else {
 			// It's not in the artifacts, so we need to enqueue a job to prepare it.
@@ -599,20 +651,26 @@ async fn handle_prepare_done(
 			never!("the artifact is already prepared: {:?}", artifact_id);
 			return Ok(())
 		},
-		Some(ArtifactState::FailedToProcess(_)) => {
+		Some(ArtifactState::FailedToProcess { .. }) => {
 			// The reasoning is similar to the above, the artifact cannot be
 			// processed at this point.
 			never!("the artifact is already processed unsuccessfully: {:?}", artifact_id);
 			return Ok(())
 		},
-		Some(state @ ArtifactState::Preparing { waiting_for_response: _ }) => state,
+		Some(state @ ArtifactState::Preparing { .. }) => state,
 	};
 
-	if let ArtifactState::Preparing { waiting_for_response } = state {
+	let num_failures = if let ArtifactState::Preparing { waiting_for_response, num_failures } =
+		state
+	{
 		for result_sender in waiting_for_response.drain(..) {
 			let _ = result_sender.send(result.clone());
 		}
-	}
+		num_failures
+	} else {
+		never!("The reasoning is similar to the above, the artifact can only be preparing at this point; qed");
+		return Ok(())
+	};
 
 	// It's finally time to dispatch all the execution requests that were waiting for this artifact
 	// to be prepared.
@@ -644,7 +702,11 @@ async fn handle_prepare_done(
 
 	*state = match result {
 		Ok(()) => ArtifactState::Prepared { last_time_needed: SystemTime::now() },
-		Err(error) => ArtifactState::FailedToProcess(error.clone()),
+		Err(error) => ArtifactState::FailedToProcess {
+			last_time_failed: SystemTime::now(),
+			num_failures: *num_failures + 1,
+			error: error.clone(),
+		},
 	};
 
 	Ok(())
@@ -707,6 +769,24 @@ async fn sweeper_task(mut sweeper_rx: mpsc::Receiver<PathBuf>) {
 	}
 }
 
+/// Check if the conditions to retry a prepare job have been met.
+fn can_retry_prepare_after_failure(
+	last_time_failed: SystemTime,
+	num_failures: u32,
+	error: &PrepareError,
+) -> bool {
+	use PrepareError::*;
+	match error {
+		// Gracefully returned an error, so it will probably be reproducible. Don't retry.
+		Prevalidation(_) | Preparation(_) => false,
+		// Retry if the retry cooldown has elapsed and if we have already retried less than
+		// `NUM_PREPARE_RETRIES` times.
+		Panic(_) | TimedOut | DidNotMakeIt =>
+			SystemTime::now() >= last_time_failed + PREPARE_FAILURE_COOLDOWN &&
+				num_failures <= NUM_PREPARE_RETRIES,
+	}
+}
+
 /// A stream that yields a pulse continuously at a given interval.
 fn pulse_every(interval: std::time::Duration) -> impl futures::Stream<Item = ()> {
 	futures::stream::unfold(interval, {
@@ -834,6 +914,25 @@ mod tests {
 				.await
 		}
 
+		async fn poll_ensure_to_prepare_queue_is_empty(&mut self) {
+			use futures_timer::Delay;
+
+			let to_prepare_queue_rx = &mut self.to_prepare_queue_rx;
+			run_until(
+				&mut self.run,
+				async {
+					futures::select! {
+						_ = Delay::new(Duration::from_millis(500)).fuse() => (),
+						_ = to_prepare_queue_rx.next().fuse() => {
+							panic!("the prepare queue is supposed to be empty")
+						}
+					}
+				}
+				.boxed(),
+			)
+			.await
+		}
+
 		async fn poll_ensure_to_execute_queue_is_empty(&mut self) {
 			use futures_timer::Delay;
 
@@ -844,7 +943,7 @@ mod tests {
 					futures::select! {
 						_ = Delay::new(Duration::from_millis(500)).fuse() => (),
 						_ = to_execute_queue_rx.next().fuse() => {
-							panic!("the execute queue supposed to be empty")
+							panic!("the execute queue is supposed to be empty")
 						}
 					}
 				}
@@ -1168,6 +1267,228 @@ mod tests {
 		}
 	}
 
+	// Test that multiple prechecking requests do not trigger preparation retries if the first one
+	// failed.
+	#[async_std::test]
+	async fn test_precheck_prepare_retry() {
+		let mut test = Builder::default().build();
+		let mut host = test.host_handle();
+
+		// Submit a precheck request that fails.
+		let (result_tx, _result_rx) = oneshot::channel();
+		host.precheck_pvf(Pvf::from_discriminator(1), result_tx).await.unwrap();
+
+		// The queue received the prepare request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+		// Send a PrepareError.
+		test.from_prepare_queue_tx
+			.send(prepare::FromQueue {
+				artifact_id: artifact_id(1),
+				result: Err(PrepareError::TimedOut),
+			})
+			.await
+			.unwrap();
+
+		// Submit another precheck request.
+		let (result_tx_2, _result_rx_2) = oneshot::channel();
+		host.precheck_pvf(Pvf::from_discriminator(1), result_tx_2).await.unwrap();
+
+		// Assert the prepare queue is empty.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+
+		// Pause for enough time to reset the cooldown for this failed prepare request.
+		futures_timer::Delay::new(PREPARE_FAILURE_COOLDOWN).await;
+
+		// Submit another precheck request.
+		let (result_tx_3, _result_rx_3) = oneshot::channel();
+		host.precheck_pvf(Pvf::from_discriminator(1), result_tx_3).await.unwrap();
+
+		// Assert the prepare queue is empty - we do not retry for precheck requests.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+	}
+
+	// Test that multiple execution requests trigger preparation retries if the first one failed due
+	// to a potentially non-reproducible error.
+	#[async_std::test]
+	async fn test_execute_prepare_retry() {
+		let mut test = Builder::default().build();
+		let mut host = test.host_handle();
+
+		// Submit a execute request that fails.
+		let (result_tx, _result_rx) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx,
+		)
+		.await
+		.unwrap();
+
+		// The queue received the prepare request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+		// Send a PrepareError.
+		test.from_prepare_queue_tx
+			.send(prepare::FromQueue {
+				artifact_id: artifact_id(1),
+				result: Err(PrepareError::TimedOut),
+			})
+			.await
+			.unwrap();
+
+		// Submit another execute request.
+		let (result_tx_2, _result_rx_2) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx_2,
+		)
+		.await
+		.unwrap();
+
+		// Assert the prepare queue is empty.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+
+		// Pause for enough time to reset the cooldown for this failed prepare request.
+		futures_timer::Delay::new(PREPARE_FAILURE_COOLDOWN).await;
+
+		// Submit another execute request.
+		let (result_tx_3, _result_rx_3) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx_3,
+		)
+		.await
+		.unwrap();
+
+		// Assert the prepare queue contains the request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+	}
+
+	// Test that multiple execution requests don't trigger preparation retries if the first one
+	// failed due to reproducible error (e.g. Prevalidation).
+	#[async_std::test]
+	async fn test_execute_prepare_no_retry() {
+		let mut test = Builder::default().build();
+		let mut host = test.host_handle();
+
+		// Submit a execute request that fails.
+		let (result_tx, _result_rx) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx,
+		)
+		.await
+		.unwrap();
+
+		// The queue received the prepare request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+		// Send a PrepareError.
+		test.from_prepare_queue_tx
+			.send(prepare::FromQueue {
+				artifact_id: artifact_id(1),
+				result: Err(PrepareError::Prevalidation("reproducible error".into())),
+			})
+			.await
+			.unwrap();
+
+		// Submit another execute request.
+		let (result_tx_2, _result_rx_2) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx_2,
+		)
+		.await
+		.unwrap();
+
+		// Assert the prepare queue is empty.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+
+		// Pause for enough time to reset the cooldown for this failed prepare request.
+		futures_timer::Delay::new(PREPARE_FAILURE_COOLDOWN).await;
+
+		// Submit another execute request.
+		let (result_tx_3, _result_rx_3) = oneshot::channel();
+		host.execute_pvf(
+			Pvf::from_discriminator(1),
+			TEST_EXECUTION_TIMEOUT,
+			b"pvf".to_vec(),
+			Priority::Critical,
+			result_tx_3,
+		)
+		.await
+		.unwrap();
+
+		// Assert the prepare queue is empty - we do not retry for prevalidation errors.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+	}
+
+	// Test that multiple heads-up requests trigger preparation retries if the first one failed.
+	#[async_std::test]
+	async fn test_heads_up_prepare_retry() {
+		let mut test = Builder::default().build();
+		let mut host = test.host_handle();
+
+		// Submit a heads-up request that fails.
+		host.heads_up(vec![Pvf::from_discriminator(1)]).await.unwrap();
+
+		// The queue received the prepare request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+		// Send a PrepareError.
+		test.from_prepare_queue_tx
+			.send(prepare::FromQueue {
+				artifact_id: artifact_id(1),
+				result: Err(PrepareError::TimedOut),
+			})
+			.await
+			.unwrap();
+
+		// Submit another heads-up request.
+		host.heads_up(vec![Pvf::from_discriminator(1)]).await.unwrap();
+
+		// Assert the prepare queue is empty.
+		test.poll_ensure_to_prepare_queue_is_empty().await;
+
+		// Pause for enough time to reset the cooldown for this failed prepare request.
+		futures_timer::Delay::new(PREPARE_FAILURE_COOLDOWN).await;
+
+		// Submit another heads-up request.
+		host.heads_up(vec![Pvf::from_discriminator(1)]).await.unwrap();
+
+		// Assert the prepare queue contains the request.
+		assert_matches!(
+			test.poll_and_recv_to_prepare_queue().await,
+			prepare::ToQueue::Enqueue { .. }
+		);
+	}
+
 	#[async_std::test]
 	async fn cancellation() {
 		let mut test = Builder::default().build();
diff --git a/node/service/Cargo.toml b/node/service/Cargo.toml
index 82109f2e6ce4..e6e073546a13 100644
--- a/node/service/Cargo.toml
+++ b/node/service/Cargo.toml
@@ -71,7 +71,8 @@ serde_json = "1.0.81"
 thiserror = "1.0.31"
 kvdb = "0.12.0"
 kvdb-rocksdb = { version = "0.16.0", optional = true }
-parity-db = { version = "0.3.16", optional = true }
+parity-db = { version = "0.4.2", optional = true }
+
 async-trait = "0.1.57"
 lru = "0.8"
 
diff --git a/node/service/src/lib.rs b/node/service/src/lib.rs
index 3619d05c7592..18218a8aba8e 100644
--- a/node/service/src/lib.rs
+++ b/node/service/src/lib.rs
@@ -943,7 +943,8 @@ where
 	let parachains_db = open_database(&config.database)?;
 
 	let approval_voting_config = ApprovalVotingConfig {
-		col_data: parachains_db::REAL_COLUMNS.col_approval_data,
+		col_approval_data: parachains_db::REAL_COLUMNS.col_approval_data,
+		col_session_data: parachains_db::REAL_COLUMNS.col_session_window_data,
 		slot_duration_millis: slot_duration.as_millis() as u64,
 	};
 
@@ -966,7 +967,8 @@ where
 	};
 
 	let dispute_coordinator_config = DisputeCoordinatorConfig {
-		col_data: parachains_db::REAL_COLUMNS.col_dispute_coordinator_data,
+		col_dispute_data: parachains_db::REAL_COLUMNS.col_dispute_coordinator_data,
+		col_session_data: parachains_db::REAL_COLUMNS.col_session_window_data,
 	};
 
 	let rpc_handlers = service::spawn_tasks(service::SpawnTasksParams {
@@ -1537,7 +1539,8 @@ fn revert_chain_selection(db: Arc<dyn Database>, hash: Hash) -> sp_blockchain::R
 
 fn revert_approval_voting(db: Arc<dyn Database>, hash: Hash) -> sp_blockchain::Result<()> {
 	let config = approval_voting_subsystem::Config {
-		col_data: parachains_db::REAL_COLUMNS.col_approval_data,
+		col_approval_data: parachains_db::REAL_COLUMNS.col_approval_data,
+		col_session_data: parachains_db::REAL_COLUMNS.col_session_window_data,
 		slot_duration_millis: Default::default(),
 	};
 
diff --git a/node/service/src/parachains_db/mod.rs b/node/service/src/parachains_db/mod.rs
index de12a8ac1a32..74e7e13dc657 100644
--- a/node/service/src/parachains_db/mod.rs
+++ b/node/service/src/parachains_db/mod.rs
@@ -23,6 +23,7 @@ mod upgrade;
 
 const LOG_TARGET: &str = "parachain::db";
 
+/// Column configuration per version.
 #[cfg(any(test, feature = "full-node"))]
 pub(crate) mod columns {
 	pub mod v0 {
@@ -31,12 +32,17 @@ pub(crate) mod columns {
 
 	pub mod v1 {
 		pub const NUM_COLUMNS: u32 = 5;
+	}
 
+	pub mod v2 {
+		pub const NUM_COLUMNS: u32 = 6;
 		pub const COL_AVAILABILITY_DATA: u32 = 0;
 		pub const COL_AVAILABILITY_META: u32 = 1;
 		pub const COL_APPROVAL_DATA: u32 = 2;
 		pub const COL_CHAIN_SELECTION_DATA: u32 = 3;
 		pub const COL_DISPUTE_COORDINATOR_DATA: u32 = 4;
+		pub const COL_SESSION_WINDOW_DATA: u32 = 5;
+
 		pub const ORDERED_COL: &[u32] =
 			&[COL_AVAILABILITY_META, COL_CHAIN_SELECTION_DATA, COL_DISPUTE_COORDINATOR_DATA];
 	}
@@ -56,16 +62,19 @@ pub struct ColumnsConfig {
 	pub col_chain_selection_data: u32,
 	/// The column used by dispute coordinator for data.
 	pub col_dispute_coordinator_data: u32,
+	/// The column used for session window data.
+	pub col_session_window_data: u32,
 }
 
 /// The real columns used by the parachains DB.
 #[cfg(any(test, feature = "full-node"))]
 pub const REAL_COLUMNS: ColumnsConfig = ColumnsConfig {
-	col_availability_data: columns::v1::COL_AVAILABILITY_DATA,
-	col_availability_meta: columns::v1::COL_AVAILABILITY_META,
-	col_approval_data: columns::v1::COL_APPROVAL_DATA,
-	col_chain_selection_data: columns::v1::COL_CHAIN_SELECTION_DATA,
-	col_dispute_coordinator_data: columns::v1::COL_DISPUTE_COORDINATOR_DATA,
+	col_availability_data: columns::v2::COL_AVAILABILITY_DATA,
+	col_availability_meta: columns::v2::COL_AVAILABILITY_META,
+	col_approval_data: columns::v2::COL_APPROVAL_DATA,
+	col_chain_selection_data: columns::v2::COL_CHAIN_SELECTION_DATA,
+	col_dispute_coordinator_data: columns::v2::COL_DISPUTE_COORDINATOR_DATA,
+	col_session_window_data: columns::v2::COL_SESSION_WINDOW_DATA,
 };
 
 #[derive(PartialEq)]
@@ -83,11 +92,18 @@ pub struct CacheSizes {
 	pub availability_meta: usize,
 	/// Cache used by approval data.
 	pub approval_data: usize,
+	/// Cache used by session window data
+	pub session_data: usize,
 }
 
 impl Default for CacheSizes {
 	fn default() -> Self {
-		CacheSizes { availability_data: 25, availability_meta: 1, approval_data: 5 }
+		CacheSizes {
+			availability_data: 25,
+			availability_meta: 1,
+			approval_data: 5,
+			session_data: 1,
+		}
 	}
 }
 
@@ -106,17 +122,20 @@ pub fn open_creating_rocksdb(
 
 	let path = root.join("parachains").join("db");
 
-	let mut db_config = DatabaseConfig::with_columns(columns::v1::NUM_COLUMNS);
+	let mut db_config = DatabaseConfig::with_columns(columns::v2::NUM_COLUMNS);
 
 	let _ = db_config
 		.memory_budget
-		.insert(columns::v1::COL_AVAILABILITY_DATA, cache_sizes.availability_data);
+		.insert(columns::v2::COL_AVAILABILITY_DATA, cache_sizes.availability_data);
+	let _ = db_config
+		.memory_budget
+		.insert(columns::v2::COL_AVAILABILITY_META, cache_sizes.availability_meta);
 	let _ = db_config
 		.memory_budget
-		.insert(columns::v1::COL_AVAILABILITY_META, cache_sizes.availability_meta);
+		.insert(columns::v2::COL_APPROVAL_DATA, cache_sizes.approval_data);
 	let _ = db_config
 		.memory_budget
-		.insert(columns::v1::COL_APPROVAL_DATA, cache_sizes.approval_data);
+		.insert(columns::v2::COL_SESSION_WINDOW_DATA, cache_sizes.session_data);
 
 	let path_str = path
 		.to_str()
@@ -127,7 +146,7 @@ pub fn open_creating_rocksdb(
 	let db = Database::open(&db_config, &path_str)?;
 	let db = polkadot_node_subsystem_util::database::kvdb_impl::DbAdapter::new(
 		db,
-		columns::v1::ORDERED_COL,
+		columns::v2::ORDERED_COL,
 	);
 
 	Ok(Arc::new(db))
@@ -147,12 +166,12 @@ pub fn open_creating_paritydb(
 	std::fs::create_dir_all(&path_str)?;
 	upgrade::try_upgrade_db(&path, DatabaseKind::ParityDB)?;
 
-	let db = parity_db::Db::open_or_create(&upgrade::paritydb_version_1_config(&path))
+	let db = parity_db::Db::open_or_create(&upgrade::paritydb_version_2_config(&path))
 		.map_err(|err| io::Error::new(io::ErrorKind::Other, format!("{:?}", err)))?;
 
 	let db = polkadot_node_subsystem_util::database::paritydb_impl::DbAdapter::new(
 		db,
-		columns::v1::ORDERED_COL,
+		columns::v2::ORDERED_COL,
 	);
 	Ok(Arc::new(db))
 }
diff --git a/node/service/src/parachains_db/upgrade.rs b/node/service/src/parachains_db/upgrade.rs
index 73321ae04c09..01d4fb62f7f6 100644
--- a/node/service/src/parachains_db/upgrade.rs
+++ b/node/service/src/parachains_db/upgrade.rs
@@ -28,7 +28,7 @@ type Version = u32;
 const VERSION_FILE_NAME: &'static str = "parachain_db_version";
 
 /// Current db version.
-const CURRENT_VERSION: Version = 1;
+const CURRENT_VERSION: Version = 2;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
@@ -36,7 +36,7 @@ pub enum Error {
 	Io(#[from] io::Error),
 	#[error("The version file format is incorrect")]
 	CorruptedVersionFile,
-	#[error("Future version (expected {current:?}, found {got:?})")]
+	#[error("Parachains DB has a future version (expected {current:?}, found {got:?})")]
 	FutureVersion { current: Version, got: Version },
 }
 
@@ -56,6 +56,8 @@ pub(crate) fn try_upgrade_db(db_path: &Path, db_kind: DatabaseKind) -> Result<()
 		match get_db_version(db_path)? {
 			// 0 -> 1 migration
 			Some(0) => migrate_from_version_0_to_1(db_path, db_kind)?,
+			// 1 -> 2 migration
+			Some(1) => migrate_from_version_1_to_2(db_path, db_kind)?,
 			// Already at current version, do nothing.
 			Some(CURRENT_VERSION) => (),
 			// This is an arbitrary future version, we don't handle it.
@@ -112,6 +114,19 @@ fn migrate_from_version_0_to_1(path: &Path, db_kind: DatabaseKind) -> Result<(),
 	})
 }
 
+fn migrate_from_version_1_to_2(path: &Path, db_kind: DatabaseKind) -> Result<(), Error> {
+	gum::info!(target: LOG_TARGET, "Migrating parachains db from version 1 to version 2 ...");
+
+	match db_kind {
+		DatabaseKind::ParityDB => paritydb_migrate_from_version_1_to_2(path),
+		DatabaseKind::RocksDB => rocksdb_migrate_from_version_1_to_2(path),
+	}
+	.and_then(|result| {
+		gum::info!(target: LOG_TARGET, "Migration complete! ");
+		Ok(result)
+	})
+}
+
 /// Migration from version 0 to version 1:
 /// * the number of columns has changed from 3 to 5;
 fn rocksdb_migrate_from_version_0_to_1(path: &Path) -> Result<(), Error> {
@@ -129,6 +144,22 @@ fn rocksdb_migrate_from_version_0_to_1(path: &Path) -> Result<(), Error> {
 	Ok(())
 }
 
+/// Migration from version 1 to version 2:
+/// * the number of columns has changed from 5 to 6;
+fn rocksdb_migrate_from_version_1_to_2(path: &Path) -> Result<(), Error> {
+	use kvdb_rocksdb::{Database, DatabaseConfig};
+
+	let db_path = path
+		.to_str()
+		.ok_or_else(|| super::other_io_error("Invalid database path".into()))?;
+	let db_cfg = DatabaseConfig::with_columns(super::columns::v1::NUM_COLUMNS);
+	let mut db = Database::open(&db_cfg, db_path)?;
+
+	db.add_column()?;
+
+	Ok(())
+}
+
 // This currently clears columns which had their configs altered between versions.
 // The columns to be changed are constrained by the `allowed_columns` vector.
 fn paritydb_fix_columns(
@@ -190,7 +221,18 @@ fn paritydb_fix_columns(
 pub(crate) fn paritydb_version_1_config(path: &Path) -> parity_db::Options {
 	let mut options =
 		parity_db::Options::with_columns(&path, super::columns::v1::NUM_COLUMNS as u8);
-	for i in columns::v1::ORDERED_COL {
+	for i in columns::v2::ORDERED_COL {
+		options.columns[*i as usize].btree_index = true;
+	}
+
+	options
+}
+
+/// Database configuration for version 2.
+pub(crate) fn paritydb_version_2_config(path: &Path) -> parity_db::Options {
+	let mut options =
+		parity_db::Options::with_columns(&path, super::columns::v2::NUM_COLUMNS as u8);
+	for i in columns::v2::ORDERED_COL {
 		options.columns[*i as usize].btree_index = true;
 	}
 
@@ -202,8 +244,8 @@ pub(crate) fn paritydb_version_1_config(path: &Path) -> parity_db::Options {
 pub(crate) fn paritydb_version_0_config(path: &Path) -> parity_db::Options {
 	let mut options =
 		parity_db::Options::with_columns(&path, super::columns::v1::NUM_COLUMNS as u8);
-	options.columns[super::columns::v1::COL_AVAILABILITY_META as usize].btree_index = true;
-	options.columns[super::columns::v1::COL_CHAIN_SELECTION_DATA as usize].btree_index = true;
+	options.columns[super::columns::v2::COL_AVAILABILITY_META as usize].btree_index = true;
+	options.columns[super::columns::v2::COL_CHAIN_SELECTION_DATA as usize].btree_index = true;
 
 	options
 }
@@ -218,17 +260,30 @@ fn paritydb_migrate_from_version_0_to_1(path: &Path) -> Result<(), Error> {
 	paritydb_fix_columns(
 		path,
 		paritydb_version_1_config(path),
-		vec![super::columns::v1::COL_DISPUTE_COORDINATOR_DATA],
+		vec![super::columns::v2::COL_DISPUTE_COORDINATOR_DATA],
 	)?;
 
 	Ok(())
 }
 
+/// Migration from version 1 to version 2:
+/// - add a new column for session information storage
+fn paritydb_migrate_from_version_1_to_2(path: &Path) -> Result<(), Error> {
+	let mut options = paritydb_version_1_config(path);
+
+	// Adds the session info column.
+	parity_db::Db::add_column(&mut options, Default::default())
+		.map_err(|e| other_io_error(format!("Error adding column {:?}", e)))?;
+
+	Ok(())
+}
+
 #[cfg(test)]
 mod tests {
+	use super::{columns::v2::*, *};
+
 	#[test]
-	fn test_paritydb_migrate_0_1() {
-		use super::{columns::v1::*, *};
+	fn test_paritydb_migrate_0_to_1() {
 		use parity_db::Db;
 
 		let db_dir = tempfile::tempdir().unwrap();
@@ -246,13 +301,119 @@ mod tests {
 		try_upgrade_db(&path, DatabaseKind::ParityDB).unwrap();
 
 		let db = Db::open(&paritydb_version_1_config(&path)).unwrap();
+		assert_eq!(db.get(COL_DISPUTE_COORDINATOR_DATA as u8, b"1234").unwrap(), None);
 		assert_eq!(
-			db.get(super::columns::v1::COL_DISPUTE_COORDINATOR_DATA as u8, b"1234").unwrap(),
-			None
+			db.get(COL_AVAILABILITY_META as u8, b"5678").unwrap(),
+			Some("somevalue".as_bytes().to_vec())
 		);
+	}
+
+	#[test]
+	fn test_paritydb_migrate_1_to_2() {
+		use parity_db::Db;
+
+		let db_dir = tempfile::tempdir().unwrap();
+		let path = db_dir.path();
+
+		// We need to properly set db version for upgrade to work.
+		fs::write(version_file_path(path), "1").expect("Failed to write DB version");
+
+		{
+			let db = Db::open_or_create(&paritydb_version_1_config(&path)).unwrap();
+
+			// Write some dummy data
+			db.commit(vec![(
+				COL_DISPUTE_COORDINATOR_DATA as u8,
+				b"1234".to_vec(),
+				Some(b"somevalue".to_vec()),
+			)])
+			.unwrap();
+
+			assert_eq!(db.num_columns(), columns::v1::NUM_COLUMNS as u8);
+		}
+
+		try_upgrade_db(&path, DatabaseKind::ParityDB).unwrap();
+
+		let db = Db::open(&paritydb_version_2_config(&path)).unwrap();
+
+		assert_eq!(db.num_columns(), columns::v2::NUM_COLUMNS as u8);
+
 		assert_eq!(
-			db.get(super::columns::v1::COL_AVAILABILITY_META as u8, b"5678").unwrap(),
+			db.get(COL_DISPUTE_COORDINATOR_DATA as u8, b"1234").unwrap(),
 			Some("somevalue".as_bytes().to_vec())
 		);
+
+		// Test we can write the new column.
+		db.commit(vec![(
+			COL_SESSION_WINDOW_DATA as u8,
+			b"1337".to_vec(),
+			Some(b"0xdeadb00b".to_vec()),
+		)])
+		.unwrap();
+
+		// Read back data from new column.
+		assert_eq!(
+			db.get(COL_SESSION_WINDOW_DATA as u8, b"1337").unwrap(),
+			Some("0xdeadb00b".as_bytes().to_vec())
+		);
+	}
+
+	#[test]
+	fn test_rocksdb_migrate_1_to_2() {
+		use kvdb::{DBKey, DBOp};
+		use kvdb_rocksdb::{Database, DatabaseConfig};
+		use polkadot_node_subsystem_util::database::{
+			kvdb_impl::DbAdapter, DBTransaction, KeyValueDB,
+		};
+
+		let db_dir = tempfile::tempdir().unwrap();
+		let db_path = db_dir.path().to_str().unwrap();
+		let db_cfg = DatabaseConfig::with_columns(super::columns::v1::NUM_COLUMNS);
+		let db = Database::open(&db_cfg, db_path).unwrap();
+		assert_eq!(db.num_columns(), super::columns::v1::NUM_COLUMNS as u32);
+
+		// We need to properly set db version for upgrade to work.
+		fs::write(version_file_path(db_dir.path()), "1").expect("Failed to write DB version");
+		{
+			let db = DbAdapter::new(db, columns::v2::ORDERED_COL);
+			db.write(DBTransaction {
+				ops: vec![DBOp::Insert {
+					col: COL_DISPUTE_COORDINATOR_DATA,
+					key: DBKey::from_slice(b"1234"),
+					value: b"0xdeadb00b".to_vec(),
+				}],
+			})
+			.unwrap();
+		}
+
+		try_upgrade_db(&db_dir.path(), DatabaseKind::RocksDB).unwrap();
+
+		let db_cfg = DatabaseConfig::with_columns(super::columns::v2::NUM_COLUMNS);
+		let db = Database::open(&db_cfg, db_path).unwrap();
+
+		assert_eq!(db.num_columns(), super::columns::v2::NUM_COLUMNS);
+
+		let db = DbAdapter::new(db, columns::v2::ORDERED_COL);
+
+		assert_eq!(
+			db.get(COL_DISPUTE_COORDINATOR_DATA, b"1234").unwrap(),
+			Some("0xdeadb00b".as_bytes().to_vec())
+		);
+
+		// Test we can write the new column.
+		db.write(DBTransaction {
+			ops: vec![DBOp::Insert {
+				col: COL_SESSION_WINDOW_DATA,
+				key: DBKey::from_slice(b"1337"),
+				value: b"0xdeadb00b".to_vec(),
+			}],
+		})
+		.unwrap();
+
+		// Read back data from new column.
+		assert_eq!(
+			db.get(COL_SESSION_WINDOW_DATA, b"1337").unwrap(),
+			Some("0xdeadb00b".as_bytes().to_vec())
+		);
 	}
 }
diff --git a/node/subsystem-util/Cargo.toml b/node/subsystem-util/Cargo.toml
index ab886c0c4078..d390fd2b42cc 100644
--- a/node/subsystem-util/Cargo.toml
+++ b/node/subsystem-util/Cargo.toml
@@ -34,7 +34,7 @@ sp-keystore = { git = "https://github.com/paritytech/substrate", branch = "maste
 
 kvdb = "0.12.0"
 parity-util-mem = { version = "0.12.0", default-features = false }
-parity-db = { version = "0.3.13" }
+parity-db = { version = "0.4.2"}
 
 [dev-dependencies]
 assert_matches = "1.4.0"
@@ -46,3 +46,4 @@ lazy_static = "1.4.0"
 polkadot-primitives-test-helpers = { path = "../../primitives/test-helpers" }
 kvdb-shared-tests = "0.10.0"
 tempfile = "3.1.0"
+kvdb-memorydb = "0.12.0"
diff --git a/node/subsystem-util/src/rolling_session_window.rs b/node/subsystem-util/src/rolling_session_window.rs
index 700feb2ccff8..beac31292b7d 100644
--- a/node/subsystem-util/src/rolling_session_window.rs
+++ b/node/subsystem-util/src/rolling_session_window.rs
@@ -19,8 +19,13 @@
 //! This is useful for consensus components which need to stay up-to-date about recent sessions but don't
 //! care about the state of particular blocks.
 
+use super::database::{DBTransaction, Database};
+use kvdb::{DBKey, DBOp};
+
+use parity_scale_codec::{Decode, Encode};
 pub use polkadot_node_primitives::{new_session_window_size, SessionWindowSize};
 use polkadot_primitives::v2::{BlockNumber, Hash, SessionIndex, SessionInfo};
+use std::sync::Arc;
 
 use futures::channel::oneshot;
 use polkadot_node_subsystem::{
@@ -29,7 +34,11 @@ use polkadot_node_subsystem::{
 	overseer,
 };
 
+// The window size is equal to the `approval-voting` and `dispute-coordinator` constants that
+// have been obsoleted.
+const SESSION_WINDOW_SIZE: SessionWindowSize = new_session_window_size!(6);
 const LOG_TARGET: &str = "parachain::rolling-session-window";
+const STORED_ROLLING_SESSION_WINDOW: &[u8] = b"Rolling_session_window";
 
 /// Sessions unavailable in state to cache.
 #[derive(Debug, Clone, thiserror::Error)]
@@ -94,55 +103,176 @@ pub enum SessionWindowUpdate {
 	Unchanged,
 }
 
+/// A structure to store rolling session database parameters.
+#[derive(Clone)]
+pub struct DatabaseParams {
+	/// Database reference.
+	pub db: Arc<dyn Database>,
+	/// The column which stores the rolling session info.
+	pub db_column: u32,
+}
 /// A rolling window of sessions and cached session info.
 pub struct RollingSessionWindow {
 	earliest_session: SessionIndex,
 	session_info: Vec<SessionInfo>,
 	window_size: SessionWindowSize,
+	// The option is just to enable some approval-voting tests to force feed sessions
+	// in the window without dealing with the DB.
+	db_params: Option<DatabaseParams>,
+}
+
+/// The rolling session data we persist in the database.
+#[derive(Encode, Decode, Default)]
+struct StoredWindow {
+	earliest_session: SessionIndex,
+	session_info: Vec<SessionInfo>,
 }
 
 impl RollingSessionWindow {
 	/// Initialize a new session info cache with the given window size.
+	/// Invariant: The database always contains the earliest session. Then,
+	/// we can always extend the session info vector using chain state.
 	pub async fn new<Sender>(
 		mut sender: Sender,
-		window_size: SessionWindowSize,
 		block_hash: Hash,
+		db_params: DatabaseParams,
 	) -> Result<Self, SessionsUnavailable>
 	where
 		Sender: overseer::SubsystemSender<RuntimeApiMessage>
 			+ overseer::SubsystemSender<ChainApiMessage>,
 	{
+		// At first, determine session window start using the chain state.
 		let session_index = get_session_index_for_child(&mut sender, block_hash).await?;
 		let earliest_non_finalized_block_session =
 			Self::earliest_non_finalized_block_session(&mut sender).await?;
 
 		// This will increase the session window to cover the full unfinalized chain.
-		let window_start = std::cmp::min(
-			session_index.saturating_sub(window_size.get() - 1),
+		let on_chain_window_start = std::cmp::min(
+			session_index.saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
 			earliest_non_finalized_block_session,
 		);
 
-		match load_all_sessions(&mut sender, block_hash, window_start, session_index).await {
-			Err(kind) => Err(SessionsUnavailable {
-				kind,
-				info: Some(SessionsUnavailableInfo {
-					window_start,
-					window_end: session_index,
-					block_hash,
+		// Fetch session information from DB.
+		let maybe_stored_window = Self::db_load(db_params.clone());
+
+		// Get the DB stored sessions and recompute window start based on DB data.
+		let (mut window_start, stored_sessions) =
+			if let Some(mut stored_window) = maybe_stored_window {
+				// Check if DB is ancient.
+				if earliest_non_finalized_block_session >
+					stored_window.earliest_session + stored_window.session_info.len() as u32
+				{
+					// If ancient, we scrap it and fetch from chain state.
+					stored_window.session_info.clear();
+				}
+
+				// The session window might extend beyond the last finalized block, but that's fine as we'll prune it at
+				// next update.
+				let window_start = if stored_window.session_info.len() > 0 {
+					// If there is at least one entry in db, we always take the DB as source of truth.
+					stored_window.earliest_session
+				} else {
+					on_chain_window_start
+				};
+
+				(window_start, stored_window.session_info)
+			} else {
+				(on_chain_window_start, Vec::new())
+			};
+
+		// Compute the amount of sessions missing from the window that will be fetched from chain state.
+		let sessions_missing_count = session_index
+			.saturating_sub(window_start)
+			.saturating_add(1)
+			.saturating_sub(stored_sessions.len() as u32);
+
+		// Extend from chain state.
+		let sessions = if sessions_missing_count > 0 {
+			match extend_sessions_from_chain_state(
+				stored_sessions,
+				&mut sender,
+				block_hash,
+				&mut window_start,
+				session_index,
+			)
+			.await
+			{
+				Err(kind) => Err(SessionsUnavailable {
+					kind,
+					info: Some(SessionsUnavailableInfo {
+						window_start,
+						window_end: session_index,
+						block_hash,
+					}),
 				}),
-			}),
-			Ok(s) => Ok(Self { earliest_session: window_start, session_info: s, window_size }),
+				Ok(sessions) => Ok(sessions),
+			}?
+		} else {
+			// There are no new sessions to be fetched from chain state.
+			Vec::new()
+		};
+
+		Ok(Self {
+			earliest_session: window_start,
+			session_info: sessions,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(db_params),
+		})
+	}
+
+	// Load session information from the parachains db.
+	fn db_load(db_params: DatabaseParams) -> Option<StoredWindow> {
+		match db_params.db.get(db_params.db_column, STORED_ROLLING_SESSION_WINDOW).ok()? {
+			None => None,
+			Some(raw) => {
+				let maybe_decoded = StoredWindow::decode(&mut &raw[..]).map(Some);
+				match maybe_decoded {
+					Ok(decoded) => decoded,
+					Err(err) => {
+						gum::warn!(
+							target: LOG_TARGET,
+							?err,
+							"Failed decoding db entry; will start with onchain session infos and self-heal DB entry on next update."
+						);
+						None
+					},
+				}
+			},
+		}
+	}
+
+	// Saves/Updates all sessions in the database.
+	// TODO: https://github.com/paritytech/polkadot/issues/6144
+	fn db_save(&mut self, stored_window: StoredWindow) {
+		if let Some(db_params) = self.db_params.as_ref() {
+			match db_params.db.write(DBTransaction {
+				ops: vec![DBOp::Insert {
+					col: db_params.db_column,
+					key: DBKey::from_slice(STORED_ROLLING_SESSION_WINDOW),
+					value: stored_window.encode(),
+				}],
+			}) {
+				Ok(_) => {},
+				Err(err) => {
+					gum::warn!(target: LOG_TARGET, ?err, "Failed writing db entry");
+				},
+			}
 		}
 	}
 
 	/// Initialize a new session info cache with the given window size and
 	/// initial data.
+	/// This is only used in `approval voting` tests.
 	pub fn with_session_info(
-		window_size: SessionWindowSize,
 		earliest_session: SessionIndex,
 		session_info: Vec<SessionInfo>,
 	) -> Self {
-		RollingSessionWindow { earliest_session, session_info, window_size }
+		RollingSessionWindow {
+			earliest_session,
+			session_info,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: None,
+		}
 	}
 
 	/// Access the session info for the given session index, if stored within the window.
@@ -262,11 +392,6 @@ impl RollingSessionWindow {
 			+ overseer::SubsystemSender<ChainApiMessage>,
 	{
 		let session_index = get_session_index_for_child(sender, block_hash).await?;
-		let earliest_non_finalized_block_session =
-			Self::earliest_non_finalized_block_session(sender).await?;
-
-		let old_window_start = self.earliest_session;
-
 		let latest = self.latest_session();
 
 		// Either cached or ancient.
@@ -274,6 +399,10 @@ impl RollingSessionWindow {
 			return Ok(SessionWindowUpdate::Unchanged)
 		}
 
+		let earliest_non_finalized_block_session =
+			Self::earliest_non_finalized_block_session(sender).await?;
+
+		let old_window_start = self.earliest_session;
 		let old_window_end = latest;
 
 		// Ensure we keep sessions up to last finalized block by adjusting the window start.
@@ -283,16 +412,34 @@ impl RollingSessionWindow {
 			earliest_non_finalized_block_session,
 		);
 
-		// keep some of the old window, if applicable.
-		let overlap_start = window_start.saturating_sub(old_window_start);
+		// Never look back past earliest session, since if sessions beyond were not needed or available
+		// in the past remains valid for the future (window only advances forward).
+		let mut window_start = std::cmp::max(window_start, self.earliest_session);
+
+		let mut sessions = self.session_info.clone();
+		let sessions_out_of_window = window_start.saturating_sub(old_window_start) as usize;
 
-		let fresh_start = if latest < window_start { window_start } else { latest + 1 };
+		let sessions = if sessions_out_of_window < sessions.len() {
+			// Drop sessions based on how much the window advanced.
+			sessions.split_off((window_start as usize).saturating_sub(old_window_start as usize))
+		} else {
+			// Window has jumped such that we need to fetch all sessions from on chain.
+			Vec::new()
+		};
 
-		match load_all_sessions(sender, block_hash, fresh_start, session_index).await {
+		match extend_sessions_from_chain_state(
+			sessions,
+			sender,
+			block_hash,
+			&mut window_start,
+			session_index,
+		)
+		.await
+		{
 			Err(kind) => Err(SessionsUnavailable {
 				kind,
 				info: Some(SessionsUnavailableInfo {
-					window_start: fresh_start,
+					window_start,
 					window_end: session_index,
 					block_hash,
 				}),
@@ -305,15 +452,19 @@ impl RollingSessionWindow {
 					new_window_end: session_index,
 				};
 
-				let outdated = std::cmp::min(overlap_start as usize, self.session_info.len());
-				self.session_info.drain(..outdated);
-				self.session_info.extend(s);
+				self.session_info = s;
+
 				// we need to account for this case:
 				// window_start ................................... session_index
 				//              old_window_start ........... latest
 				let new_earliest = std::cmp::max(window_start, old_window_start);
 				self.earliest_session = new_earliest;
 
+				// Update current window in DB.
+				self.db_save(StoredWindow {
+					earliest_session: self.earliest_session,
+					session_info: self.session_info.clone(),
+				});
 				Ok(update)
 			},
 		}
@@ -354,13 +505,23 @@ async fn get_session_index_for_child(
 	}
 }
 
-async fn load_all_sessions(
+/// Attempts to extend db stored sessions with sessions missing between `start` and up to `end_inclusive`.
+/// Runtime session info fetching errors are ignored if that doesn't create a gap in the window.
+async fn extend_sessions_from_chain_state(
+	stored_sessions: Vec<SessionInfo>,
 	sender: &mut impl overseer::SubsystemSender<RuntimeApiMessage>,
 	block_hash: Hash,
-	start: SessionIndex,
+	window_start: &mut SessionIndex,
 	end_inclusive: SessionIndex,
 ) -> Result<Vec<SessionInfo>, SessionsUnavailableReason> {
-	let mut v = Vec::new();
+	// Start from the db sessions.
+	let mut sessions = stored_sessions;
+	// We allow session fetch failures only if we won't create a gap in the window by doing so.
+	// If `allow_failure` is set to true here, fetching errors are ignored until we get a first session.
+	let mut allow_failure = sessions.is_empty();
+
+	let start = *window_start + sessions.len() as u32;
+
 	for i in start..=end_inclusive {
 		let (tx, rx) = oneshot::channel();
 		sender
@@ -370,22 +531,58 @@ async fn load_all_sessions(
 			))
 			.await;
 
-		let session_info = match rx.await {
-			Ok(Ok(Some(s))) => s,
-			Ok(Ok(None)) => return Err(SessionsUnavailableReason::Missing(i)),
-			Ok(Err(e)) => return Err(SessionsUnavailableReason::RuntimeApi(e)),
-			Err(canceled) => return Err(SessionsUnavailableReason::RuntimeApiUnavailable(canceled)),
+		match rx.await {
+			Ok(Ok(Some(session_info))) => {
+				// We do not allow failure anymore after having at least 1 session in window.
+				allow_failure = false;
+				sessions.push(session_info);
+			},
+			Ok(Ok(None)) if !allow_failure => return Err(SessionsUnavailableReason::Missing(i)),
+			Ok(Ok(None)) => {
+				// Handle `allow_failure` true.
+				// If we didn't get the session, we advance window start.
+				*window_start += 1;
+				gum::debug!(
+					target: LOG_TARGET,
+					session = ?i,
+					"Session info missing from runtime."
+				);
+			},
+			Ok(Err(e)) if !allow_failure => return Err(SessionsUnavailableReason::RuntimeApi(e)),
+			Err(canceled) if !allow_failure =>
+				return Err(SessionsUnavailableReason::RuntimeApiUnavailable(canceled)),
+			Ok(Err(err)) => {
+				// Handle `allow_failure` true.
+				// If we didn't get the session, we advance window start.
+				*window_start += 1;
+				gum::debug!(
+					target: LOG_TARGET,
+					session = ?i,
+					?err,
+					"Error while fetching session information."
+				);
+			},
+			Err(err) => {
+				// Handle `allow_failure` true.
+				// If we didn't get the session, we advance window start.
+				*window_start += 1;
+				gum::debug!(
+					target: LOG_TARGET,
+					session = ?i,
+					?err,
+					"Channel error while fetching session information."
+				);
+			},
 		};
-
-		v.push(session_info);
 	}
 
-	Ok(v)
+	Ok(sessions)
 }
 
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use crate::database::kvdb_impl::DbAdapter;
 	use assert_matches::assert_matches;
 	use polkadot_node_subsystem::{
 		messages::{AllMessages, AvailabilityRecoveryMessage},
@@ -395,7 +592,16 @@ mod tests {
 	use polkadot_primitives::v2::Header;
 	use sp_core::testing::TaskExecutor;
 
-	pub const TEST_WINDOW_SIZE: SessionWindowSize = new_session_window_size!(6);
+	const SESSION_DATA_COL: u32 = 0;
+
+	const NUM_COLUMNS: u32 = 1;
+
+	fn dummy_db_params() -> DatabaseParams {
+		let db = kvdb_memorydb::create(NUM_COLUMNS);
+		let db = DbAdapter::new(db, &[]);
+		let db: Arc<dyn Database> = Arc::new(db);
+		DatabaseParams { db, db_column: SESSION_DATA_COL }
+	}
 
 	fn dummy_session_info(index: SessionIndex) -> SessionInfo {
 		SessionInfo {
@@ -420,7 +626,10 @@ mod tests {
 		session: SessionIndex,
 		window: Option<RollingSessionWindow>,
 		expect_requests_from: SessionIndex,
-	) {
+		db_params: Option<DatabaseParams>,
+	) -> RollingSessionWindow {
+		let db_params = db_params.unwrap_or(dummy_db_params());
+
 		let header = Header {
 			digest: Default::default(),
 			extrinsics_root: Default::default(),
@@ -448,9 +657,8 @@ mod tests {
 		let test_fut = {
 			Box::pin(async move {
 				let window = match window {
-					None => RollingSessionWindow::new(sender.clone(), TEST_WINDOW_SIZE, hash)
-						.await
-						.unwrap(),
+					None =>
+						RollingSessionWindow::new(sender.clone(), hash, db_params).await.unwrap(),
 					Some(mut window) => {
 						window.cache_session_info_for_head(sender, hash).await.unwrap();
 						window
@@ -461,6 +669,8 @@ mod tests {
 					window.session_info,
 					(expected_start_session..=session).map(dummy_session_info).collect::<Vec<_>>(),
 				);
+
+				window
 			})
 		};
 
@@ -522,12 +732,43 @@ mod tests {
 			}
 		});
 
-		futures::executor::block_on(futures::future::join(test_fut, aux_fut));
+		let (window, _) = futures::executor::block_on(futures::future::join(test_fut, aux_fut));
+		window
+	}
+
+	#[test]
+	fn cache_session_info_start_empty_db() {
+		let db_params = dummy_db_params();
+
+		let window = cache_session_info_test(
+			(10 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			10,
+			None,
+			(10 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			Some(db_params.clone()),
+		);
+
+		let window = cache_session_info_test(
+			(11 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			11,
+			Some(window),
+			11,
+			None,
+		);
+		assert_eq!(window.session_info.len(), SESSION_WINDOW_SIZE.get() as usize);
+
+		cache_session_info_test(
+			(11 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			12,
+			None,
+			12,
+			Some(db_params),
+		);
 	}
 
 	#[test]
 	fn cache_session_info_first_early() {
-		cache_session_info_test(0, 1, None, 0);
+		cache_session_info_test(0, 1, None, 0, None);
 	}
 
 	#[test]
@@ -535,19 +776,21 @@ mod tests {
 		let window = RollingSessionWindow {
 			earliest_session: 1,
 			session_info: vec![dummy_session_info(1)],
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
-		cache_session_info_test(1, 2, Some(window), 2);
+		cache_session_info_test(1, 2, Some(window), 2, None);
 	}
 
 	#[test]
 	fn cache_session_info_first_late() {
 		cache_session_info_test(
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
 			100,
 			None,
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			None,
 		);
 	}
 
@@ -560,48 +803,88 @@ mod tests {
 				dummy_session_info(51),
 				dummy_session_info(52),
 			],
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
 		cache_session_info_test(
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
 			100,
 			Some(window),
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			None,
 		);
 	}
 
 	#[test]
 	fn cache_session_info_roll_full() {
-		let start = 99 - (TEST_WINDOW_SIZE.get() - 1);
+		let start = 99 - (SESSION_WINDOW_SIZE.get() - 1);
 		let window = RollingSessionWindow {
 			earliest_session: start,
 			session_info: (start..=99).map(dummy_session_info).collect(),
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
 		cache_session_info_test(
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
 			100,
 			Some(window),
 			100, // should only make one request.
+			None,
+		);
+	}
+
+	#[test]
+	fn cache_session_info_roll_many_full_db() {
+		let db_params = dummy_db_params();
+		let start = 97 - (SESSION_WINDOW_SIZE.get() - 1);
+		let window = RollingSessionWindow {
+			earliest_session: start,
+			session_info: (start..=97).map(dummy_session_info).collect(),
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(db_params.clone()),
+		};
+
+		cache_session_info_test(
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			100,
+			Some(window),
+			98,
+			None,
+		);
+
+		// We expect the session to be populated from DB, and only fetch 101 from on chain.
+		cache_session_info_test(
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
+			101,
+			None,
+			101,
+			Some(db_params.clone()),
 		);
+
+		// Session warps in the future.
+		let window = cache_session_info_test(195, 200, None, 195, Some(db_params));
+
+		assert_eq!(window.session_info.len(), SESSION_WINDOW_SIZE.get() as usize);
 	}
 
 	#[test]
 	fn cache_session_info_roll_many_full() {
-		let start = 97 - (TEST_WINDOW_SIZE.get() - 1);
+		let start = 97 - (SESSION_WINDOW_SIZE.get() - 1);
 		let window = RollingSessionWindow {
 			earliest_session: start,
 			session_info: (start..=97).map(dummy_session_info).collect(),
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
 		cache_session_info_test(
-			(100 as SessionIndex).saturating_sub(TEST_WINDOW_SIZE.get() - 1),
+			(100 as SessionIndex).saturating_sub(SESSION_WINDOW_SIZE.get() - 1),
 			100,
 			Some(window),
 			98,
+			None,
 		);
 	}
 
@@ -611,7 +894,8 @@ mod tests {
 		let window = RollingSessionWindow {
 			earliest_session: start,
 			session_info: (0..=1).map(dummy_session_info).collect(),
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
 		cache_session_info_test(
@@ -619,6 +903,7 @@ mod tests {
 			2,
 			Some(window),
 			2, // should only make one request.
+			None,
 		);
 	}
 
@@ -628,14 +913,17 @@ mod tests {
 		let window = RollingSessionWindow {
 			earliest_session: start,
 			session_info: (0..=1).map(dummy_session_info).collect(),
-			window_size: TEST_WINDOW_SIZE,
+			window_size: SESSION_WINDOW_SIZE,
+			db_params: Some(dummy_db_params()),
 		};
 
-		cache_session_info_test(0, 3, Some(window), 2);
+		let actual_window_size = window.session_info.len() as u32;
+
+		cache_session_info_test(0, 3, Some(window), actual_window_size, None);
 	}
 
 	#[test]
-	fn any_session_stretch_for_unfinalized_chain() {
+	fn cache_session_fails_for_gap_in_window() {
 		// Session index of the tip of our fake test chain.
 		let session: SessionIndex = 100;
 		let genesis_session: SessionIndex = 0;
@@ -664,7 +952,8 @@ mod tests {
 		let test_fut = {
 			let sender = ctx.sender().clone();
 			Box::pin(async move {
-				let res = RollingSessionWindow::new(sender, TEST_WINDOW_SIZE, hash).await;
+				let res = RollingSessionWindow::new(sender, hash, dummy_db_params()).await;
+
 				assert!(res.is_err());
 			})
 		};
@@ -713,6 +1002,135 @@ mod tests {
 			);
 
 			// Unfinalized chain starts at geneisis block, so session 0 is how far we stretch.
+			// First 50 sessions are missing.
+			for i in genesis_session..=50 {
+				assert_matches!(
+					handle.recv().await,
+					AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+						h,
+						RuntimeApiRequest::SessionInfo(j, s_tx),
+					)) => {
+						assert_eq!(h, hash);
+						assert_eq!(i, j);
+						let _ = s_tx.send(Ok(None));
+					}
+				);
+			}
+			// next 10 sessions are present
+			for i in 51..=60 {
+				assert_matches!(
+					handle.recv().await,
+					AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+						h,
+						RuntimeApiRequest::SessionInfo(j, s_tx),
+					)) => {
+						assert_eq!(h, hash);
+						assert_eq!(i, j);
+						let _ = s_tx.send(Ok(Some(dummy_session_info(i))));
+					}
+				);
+			}
+			// gap of 1 session
+			assert_matches!(
+				handle.recv().await,
+				AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+					h,
+					RuntimeApiRequest::SessionInfo(j, s_tx),
+				)) => {
+					assert_eq!(h, hash);
+					assert_eq!(61, j);
+					let _ = s_tx.send(Ok(None));
+				}
+			);
+		});
+
+		futures::executor::block_on(futures::future::join(test_fut, aux_fut));
+	}
+
+	#[test]
+	fn any_session_stretch_with_failure_allowed_for_unfinalized_chain() {
+		// Session index of the tip of our fake test chain.
+		let session: SessionIndex = 100;
+		let genesis_session: SessionIndex = 0;
+
+		let header = Header {
+			digest: Default::default(),
+			extrinsics_root: Default::default(),
+			number: 5,
+			state_root: Default::default(),
+			parent_hash: Default::default(),
+		};
+
+		let finalized_header = Header {
+			digest: Default::default(),
+			extrinsics_root: Default::default(),
+			number: 0,
+			state_root: Default::default(),
+			parent_hash: Default::default(),
+		};
+
+		let pool = TaskExecutor::new();
+		let (mut ctx, mut handle) = make_subsystem_context::<(), _>(pool.clone());
+
+		let hash = header.hash();
+
+		let test_fut = {
+			let sender = ctx.sender().clone();
+			Box::pin(async move {
+				let res = RollingSessionWindow::new(sender, hash, dummy_db_params()).await;
+				assert!(res.is_ok());
+				let rsw = res.unwrap();
+				// Since first 50 sessions are missing the earliest should be 50.
+				assert_eq!(rsw.earliest_session, 50);
+				assert_eq!(rsw.session_info.len(), 51);
+			})
+		};
+
+		let aux_fut = Box::pin(async move {
+			assert_matches!(
+				handle.recv().await,
+				AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+					h,
+					RuntimeApiRequest::SessionIndexForChild(s_tx),
+				)) => {
+					assert_eq!(h, hash);
+					let _ = s_tx.send(Ok(session));
+				}
+			);
+
+			assert_matches!(
+				handle.recv().await,
+				AllMessages::ChainApi(ChainApiMessage::FinalizedBlockNumber(
+					s_tx,
+				)) => {
+					let _ = s_tx.send(Ok(finalized_header.number));
+				}
+			);
+
+			assert_matches!(
+				handle.recv().await,
+				AllMessages::ChainApi(ChainApiMessage::FinalizedBlockHash(
+					block_number,
+					s_tx,
+				)) => {
+					assert_eq!(block_number, finalized_header.number);
+					let _ = s_tx.send(Ok(Some(finalized_header.hash())));
+				}
+			);
+
+			assert_matches!(
+				handle.recv().await,
+				AllMessages::RuntimeApi(RuntimeApiMessage::Request(
+					h,
+					RuntimeApiRequest::SessionIndexForChild(s_tx),
+				)) => {
+					assert_eq!(h, finalized_header.hash());
+					let _ = s_tx.send(Ok(0));
+				}
+			);
+
+			// Unfinalized chain starts at geneisis block, so session 0 is how far we stretch.
+			// We also test if failure is allowed for 50 first missing sessions.
 			for i in genesis_session..=session {
 				assert_matches!(
 					handle.recv().await,
@@ -723,7 +1141,7 @@ mod tests {
 						assert_eq!(h, hash);
 						assert_eq!(i, j);
 
-						let _ = s_tx.send(Ok(if i == session {
+						let _ = s_tx.send(Ok(if i < 50 {
 							None
 						} else {
 							Some(dummy_session_info(i))
@@ -739,7 +1157,7 @@ mod tests {
 	#[test]
 	fn any_session_unavailable_for_caching_means_no_change() {
 		let session: SessionIndex = 6;
-		let start_session = session.saturating_sub(TEST_WINDOW_SIZE.get() - 1);
+		let start_session = session.saturating_sub(SESSION_WINDOW_SIZE.get() - 1);
 
 		let header = Header {
 			digest: Default::default(),
@@ -765,7 +1183,7 @@ mod tests {
 		let test_fut = {
 			let sender = ctx.sender().clone();
 			Box::pin(async move {
-				let res = RollingSessionWindow::new(sender, TEST_WINDOW_SIZE, hash).await;
+				let res = RollingSessionWindow::new(sender, hash, dummy_db_params()).await;
 				assert!(res.is_err());
 			})
 		};
@@ -857,7 +1275,7 @@ mod tests {
 			Box::pin(async move {
 				let sender = ctx.sender().clone();
 				let window =
-					RollingSessionWindow::new(sender, TEST_WINDOW_SIZE, hash).await.unwrap();
+					RollingSessionWindow::new(sender, hash, dummy_db_params()).await.unwrap();
 
 				assert_eq!(window.earliest_session, session);
 				assert_eq!(window.session_info, vec![dummy_session_info(session)]);
diff --git a/roadmap/implementers-guide/README.md b/roadmap/implementers-guide/README.md
index 1775fb44d876..7f3f8cef7e63 100644
--- a/roadmap/implementers-guide/README.md
+++ b/roadmap/implementers-guide/README.md
@@ -4,13 +4,14 @@ The implementers' guide is compiled from several source files with [`mdBook`](ht
 
 ## Hosted build
 
-This is avalible at https://paritytech.github.io/polkadot/book/
+This is available [here](https://paritytech.github.io/polkadot/book/).
 
 ## Local build
 
 To view it locally from the repo root:
 
 Ensure graphviz is installed:
+
 ```sh
 brew install graphviz # for macOS
 sudo apt-get install graphviz # for Ubuntu/Debian
@@ -19,11 +20,11 @@ sudo apt-get install graphviz # for Ubuntu/Debian
 Then install and build the book:
 
 ```sh
-cargo install mdbook mdbook-linkcheck mdbook-graphviz mdbook-mermaid
+cargo install mdbook mdbook-linkcheck mdbook-graphviz mdbook-mermaid mdbook-last-changed
 mdbook serve roadmap/implementers-guide
 open http://localhost:3000
 ```
 
 ## Specification
 
-See also the Polkadot specificaton [hosted](https://spec.polkadot.network/), and it's [source](https://github.com/w3f/polkadot-spec)).
+See also the Polkadot specification [hosted](https://spec.polkadot.network/), and its [source](https://github.com/w3f/polkadot-spec).
diff --git a/roadmap/implementers-guide/book.toml b/roadmap/implementers-guide/book.toml
index 8805ca4c38c3..0ced0e26f9a0 100644
--- a/roadmap/implementers-guide/book.toml
+++ b/roadmap/implementers-guide/book.toml
@@ -9,8 +9,14 @@ title = "The Polkadot Parachain Host Implementers' Guide"
 command = "mdbook-graphviz"
 [preprocessor.mermaid]
 command = "mdbook-mermaid"
+[preprocessor.last-changed]
+command = "mdbook-last-changed"
+renderer = ["html"]
 
 [output.html]
+additional-css = ["last-changed.css"]
 additional-js = ["mermaid.min.js", "mermaid-init.js"]
+# Repository URL used in the last-changed link.
+git-repository-url = "https://github.com/paritytech/polkadot"
 
 [output.linkcheck]
diff --git a/roadmap/implementers-guide/last-changed.css b/roadmap/implementers-guide/last-changed.css
new file mode 100644
index 000000000000..744dc6efc7ec
--- /dev/null
+++ b/roadmap/implementers-guide/last-changed.css
@@ -0,0 +1,7 @@
+footer {
+    font-size: 0.8em;
+    text-align: center;
+    margin-top: 50px;
+    border-top: 1px solid black;
+    padding: 5px 0;
+}
diff --git a/runtime/common/Cargo.toml b/runtime/common/Cargo.toml
index 9ee5de41188d..96f29eae9257 100644
--- a/runtime/common/Cargo.toml
+++ b/runtime/common/Cargo.toml
@@ -31,6 +31,7 @@ pallet-balances = { git = "https://github.com/paritytech/substrate", branch = "m
 pallet-session = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-support = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 pallet-staking = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
+pallet-staking-reward-fn = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-system = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 pallet-timestamp = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 pallet-vesting = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
@@ -84,6 +85,7 @@ std = [
 	"pallet-beefy-mmr/std",
 	"pallet-session/std",
 	"pallet-staking/std",
+	"pallet-staking-reward-fn/std",
 	"pallet-timestamp/std",
 	"pallet-vesting/std",
 	"pallet-transaction-payment/std",
diff --git a/runtime/common/src/impls.rs b/runtime/common/src/impls.rs
index 939b753092f5..2b10c79cfdff 100644
--- a/runtime/common/src/impls.rs
+++ b/runtime/common/src/impls.rs
@@ -18,6 +18,8 @@
 
 use crate::NegativeImbalance;
 use frame_support::traits::{Currency, Imbalance, OnUnbalanced};
+use primitives::v2::Balance;
+use sp_runtime::Perquintill;
 
 /// Logic for the author to get a portion of fees.
 pub struct ToAuthor<R>(sp_std::marker::PhantomData<R>);
@@ -57,6 +59,45 @@ where
 	}
 }
 
+pub fn era_payout(
+	total_staked: Balance,
+	non_gilt_issuance: Balance,
+	max_annual_inflation: Perquintill,
+	period_fraction: Perquintill,
+	auctioned_slots: u64,
+) -> (Balance, Balance) {
+	use pallet_staking_reward_fn::compute_inflation;
+	use sp_runtime::traits::Saturating;
+
+	let min_annual_inflation = Perquintill::from_rational(25u64, 1000u64);
+	let delta_annual_inflation = max_annual_inflation.saturating_sub(min_annual_inflation);
+
+	// 30% reserved for up to 60 slots.
+	let auction_proportion = Perquintill::from_rational(auctioned_slots.min(60), 200u64);
+
+	// Therefore the ideal amount at stake (as a percentage of total issuance) is 75% less the
+	// amount that we expect to be taken up with auctions.
+	let ideal_stake = Perquintill::from_percent(75).saturating_sub(auction_proportion);
+
+	let stake = Perquintill::from_rational(total_staked, non_gilt_issuance);
+	let falloff = Perquintill::from_percent(5);
+	let adjustment = compute_inflation(stake, ideal_stake, falloff);
+	let staking_inflation =
+		min_annual_inflation.saturating_add(delta_annual_inflation * adjustment);
+
+	let max_payout = period_fraction * max_annual_inflation * non_gilt_issuance;
+	let staking_payout = (period_fraction * staking_inflation) * non_gilt_issuance;
+	let rest = max_payout.saturating_sub(staking_payout);
+
+	let other_issuance = non_gilt_issuance.saturating_sub(total_staked);
+	if total_staked > other_issuance {
+		let _cap_rest = Perquintill::from_rational(other_issuance, total_staked) * staking_payout;
+		// We don't do anything with this, but if we wanted to, we could introduce a cap on the
+		// treasury amount with: `rest = rest.min(cap_rest);`
+	}
+	(staking_payout, rest)
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;
@@ -209,4 +250,44 @@ mod tests {
 			assert_eq!(Balances::free_balance(Treasury::account_id()), 8);
 		});
 	}
+
+	#[test]
+	fn compute_inflation_should_give_sensible_results() {
+		assert_eq!(
+			pallet_staking_reward_fn::compute_inflation(
+				Perquintill::from_percent(75),
+				Perquintill::from_percent(75),
+				Perquintill::from_percent(5),
+			),
+			Perquintill::one()
+		);
+		assert_eq!(
+			pallet_staking_reward_fn::compute_inflation(
+				Perquintill::from_percent(50),
+				Perquintill::from_percent(75),
+				Perquintill::from_percent(5),
+			),
+			Perquintill::from_rational(2u64, 3u64)
+		);
+		assert_eq!(
+			pallet_staking_reward_fn::compute_inflation(
+				Perquintill::from_percent(80),
+				Perquintill::from_percent(75),
+				Perquintill::from_percent(5),
+			),
+			Perquintill::from_rational(1u64, 2u64)
+		);
+	}
+
+	#[test]
+	fn era_payout_should_give_sensible_results() {
+		assert_eq!(
+			era_payout(75, 100, Perquintill::from_percent(10), Perquintill::one(), 0,),
+			(10, 0)
+		);
+		assert_eq!(
+			era_payout(80, 100, Perquintill::from_percent(10), Perquintill::one(), 0,),
+			(6, 4)
+		);
+	}
 }
diff --git a/runtime/kusama/Cargo.toml b/runtime/kusama/Cargo.toml
index 72500677c534..ec3de40ec5e6 100644
--- a/runtime/kusama/Cargo.toml
+++ b/runtime/kusama/Cargo.toml
@@ -72,7 +72,6 @@ pallet-session = { git = "https://github.com/paritytech/substrate", branch = "ma
 pallet-society = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-support = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 pallet-staking = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
-pallet-staking-reward-fn = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-system = {git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-system-rpc-runtime-api = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 pallet-timestamp = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
@@ -170,7 +169,6 @@ std = [
 	"pallet-session/std",
 	"pallet-society/std",
 	"pallet-staking/std",
-	"pallet-staking-reward-fn/std",
 	"pallet-timestamp/std",
 	"pallet-tips/std",
 	"pallet-treasury/std",
diff --git a/runtime/kusama/src/lib.rs b/runtime/kusama/src/lib.rs
index 0eb8cc0b4944..3f77ece6c86a 100644
--- a/runtime/kusama/src/lib.rs
+++ b/runtime/kusama/src/lib.rs
@@ -26,6 +26,7 @@ use primitives::v2::{
 	CoreState, GroupRotationInfo, Hash, Id as ParaId, InboundDownwardMessage, InboundHrmpMessage,
 	Moment, Nonce, OccupiedCoreAssumption, PersistedValidationData, ScrapedOnChainVotes,
 	SessionInfo, Signature, ValidationCode, ValidationCodeHash, ValidatorId, ValidatorIndex,
+	LOWEST_PUBLIC_ID,
 };
 use runtime_common::{
 	auctions, claims, crowdloan, impl_runtime_weights, impls::DealWithFees, paras_registrar,
@@ -410,6 +411,9 @@ parameter_types! {
 	pub const MaxElectableTargets: u16 = u16::MAX;
 	pub NposSolutionPriority: TransactionPriority =
 		Perbill::from_percent(90) * TransactionPriority::max_value();
+	/// Setup election pallet to support maximum winners upto 2000. This will mean Staking Pallet
+	/// cannot have active validators higher than this count.
+	pub const MaxActiveValidators: u32 = 2000;
 }
 
 generate_solution_type!(
@@ -428,6 +432,9 @@ impl onchain::Config for OnChainSeqPhragmen {
 	type Solver = SequentialPhragmen<AccountId, runtime_common::elections::OnChainAccuracy>;
 	type DataProvider = Staking;
 	type WeightInfo = weights::frame_election_provider_support::WeightInfo<Runtime>;
+	type MaxWinners = MaxActiveValidators;
+	type VotersBound = MaxElectingVoters;
+	type TargetsBound = MaxElectableTargets;
 }
 
 impl pallet_election_provider_multi_phase::MinerConfig for Runtime {
@@ -475,10 +482,15 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type MinerTxPriority = NposSolutionPriority;
 	type DataProvider = Staking;
 	#[cfg(feature = "fast-runtime")]
-	type Fallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	#[cfg(not(feature = "fast-runtime"))]
-	type Fallback = pallet_election_provider_multi_phase::NoFallback<Self>;
-	type GovernanceFallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = frame_election_provider_support::NoElection<(
+		AccountId,
+		BlockNumber,
+		Staking,
+		MaxActiveValidators,
+	)>;
+	type GovernanceFallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type Solver = SequentialPhragmen<
 		AccountId,
 		pallet_election_provider_multi_phase::SolutionAccuracyOf<Self>,
@@ -489,6 +501,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type WeightInfo = weights::pallet_election_provider_multi_phase::WeightInfo<Self>;
 	type MaxElectingVoters = MaxElectingVoters;
 	type MaxElectableTargets = MaxElectableTargets;
+	type MaxWinners = MaxActiveValidators;
 }
 
 parameter_types! {
@@ -504,45 +517,6 @@ impl pallet_bags_list::Config<VoterBagsListInstance> for Runtime {
 	type Score = sp_npos_elections::VoteWeight;
 }
 
-fn era_payout(
-	total_staked: Balance,
-	non_gilt_issuance: Balance,
-	max_annual_inflation: Perquintill,
-	period_fraction: Perquintill,
-	auctioned_slots: u64,
-) -> (Balance, Balance) {
-	use pallet_staking_reward_fn::compute_inflation;
-	use sp_arithmetic::traits::Saturating;
-
-	let min_annual_inflation = Perquintill::from_rational(25u64, 1000u64);
-	let delta_annual_inflation = max_annual_inflation.saturating_sub(min_annual_inflation);
-
-	// 30% reserved for up to 60 slots.
-	let auction_proportion = Perquintill::from_rational(auctioned_slots.min(60), 200u64);
-
-	// Therefore the ideal amount at stake (as a percentage of total issuance) is 75% less the amount that we expect
-	// to be taken up with auctions.
-	let ideal_stake = Perquintill::from_percent(75).saturating_sub(auction_proportion);
-
-	let stake = Perquintill::from_rational(total_staked, non_gilt_issuance);
-	let falloff = Perquintill::from_percent(5);
-	let adjustment = compute_inflation(stake, ideal_stake, falloff);
-	let staking_inflation =
-		min_annual_inflation.saturating_add(delta_annual_inflation * adjustment);
-
-	let max_payout = period_fraction * max_annual_inflation * non_gilt_issuance;
-	let staking_payout = (period_fraction * staking_inflation) * non_gilt_issuance;
-	let rest = max_payout.saturating_sub(staking_payout);
-
-	let other_issuance = non_gilt_issuance.saturating_sub(total_staked);
-	if total_staked > other_issuance {
-		let _cap_rest = Perquintill::from_rational(other_issuance, total_staked) * staking_payout;
-		// We don't do anything with this, but if we wanted to, we could introduce a cap on the treasury amount
-		// with: `rest = rest.min(cap_rest);`
-	}
-	(staking_payout, rest)
-}
-
 pub struct EraPayout;
 impl pallet_staking::EraPayout<Balance> for EraPayout {
 	fn era_payout(
@@ -550,13 +524,18 @@ impl pallet_staking::EraPayout<Balance> for EraPayout {
 		_total_issuance: Balance,
 		era_duration_millis: u64,
 	) -> (Balance, Balance) {
-		// TODO: #3011 Update with proper auctioned slots tracking.
-		// This should be fine for the first year of parachains.
-		let auctioned_slots: u64 = auctions::Pallet::<Runtime>::auction_counter().into();
+		// all para-ids that are currently active.
+		let auctioned_slots = Paras::parachains()
+			.into_iter()
+			// all active para-ids that do not belong to a system or common good chain is the number
+			// of parachains that we should take into account for inflation.
+			.filter(|i| *i >= LOWEST_PUBLIC_ID)
+			.count() as u64;
+
 		const MAX_ANNUAL_INFLATION: Perquintill = Perquintill::from_percent(10);
 		const MILLISECONDS_PER_YEAR: u64 = 1000 * 3600 * 24 * 36525 / 100;
 
-		era_payout(
+		runtime_common::impls::era_payout(
 			total_staked,
 			Gilt::issuance().non_gilt,
 			MAX_ANNUAL_INFLATION,
@@ -573,7 +552,7 @@ parameter_types! {
 	pub const BondingDuration: sp_staking::EraIndex = 28;
 	// 27 eras in which slashes can be cancelled (slightly less than 7 days).
 	pub const SlashDeferDuration: sp_staking::EraIndex = 27;
-	pub const MaxNominatorRewardedPerValidator: u32 = 256;
+	pub const MaxNominatorRewardedPerValidator: u32 = 512;
 	pub const OffendingValidatorsThreshold: Perbill = Perbill::from_percent(17);
 	// 24
 	pub const MaxNominations: u32 = <NposCompactSolution24 as NposSolution>::LIMIT as u32;
@@ -586,7 +565,7 @@ impl pallet_staking::Config for Runtime {
 	type UnixTime = Timestamp;
 	type CurrencyToVote = CurrencyToVote;
 	type ElectionProvider = ElectionProviderMultiPhase;
-	type GenesisElectionProvider = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type RewardRemainder = Treasury;
 	type RuntimeEvent = RuntimeEvent;
 	type Slash = Treasury;
@@ -613,6 +592,7 @@ impl pallet_staking::Config for Runtime {
 impl pallet_fast_unstake::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type Currency = Balances;
+	type BatchSize = frame_support::traits::ConstU32<64>;
 	type Deposit = frame_support::traits::ConstU128<{ CENTS * 100 }>;
 	type ControlOrigin = EitherOfDiverse<
 		EnsureRoot<AccountId>,
@@ -1473,6 +1453,7 @@ pub type Executive = frame_executive::Executive<
 		// "Properly migrate weights to v2" <https://github.com/paritytech/polkadot/pull/6091>
 		parachains_configuration::migration::v3::MigrateToV3<Runtime>,
 		pallet_election_provider_multi_phase::migrations::v1::MigrateToV1<Runtime>,
+		pallet_fast_unstake::migrations::v1::MigrateToV1<Runtime>,
 	),
 >;
 /// The payload being signed in the transactions.
@@ -1710,53 +1691,27 @@ sp_api::impl_runtime_apis! {
 	}
 
 	impl mmr::MmrApi<Block, Hash, BlockNumber> for Runtime {
-		fn generate_proof(_block_number: BlockNumber)
-			-> Result<(mmr::EncodableOpaqueLeaf, mmr::Proof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof(_leaf: mmr::EncodableOpaqueLeaf, _proof: mmr::Proof<Hash>)
-			-> Result<(), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof_stateless(
-			_root: Hash,
-			_leaf: mmr::EncodableOpaqueLeaf,
-			_proof: mmr::Proof<Hash>
-		) -> Result<(), mmr::Error> {
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
 		fn mmr_root() -> Result<Hash, mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn generate_batch_proof(_block_numbers: Vec<BlockNumber>)
-			-> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn generate_historical_batch_proof(
+		fn generate_proof(
 			_block_numbers: Vec<BlockNumber>,
-			_best_known_block_number: BlockNumber,
-		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error> {
+			_best_known_block_number: Option<BlockNumber>,
+		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::Proof<Hash>), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::BatchProof<Hash>)
+		fn verify_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::Proof<Hash>)
 			-> Result<(), mmr::Error>
 		{
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof_stateless(
+		fn verify_proof_stateless(
 			_root: Hash,
 			_leaves: Vec<mmr::EncodableOpaqueLeaf>,
-			_proof: mmr::BatchProof<Hash>
+			_proof: mmr::Proof<Hash>
 		) -> Result<(), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
diff --git a/runtime/kusama/src/tests.rs b/runtime/kusama/src/tests.rs
index 12d02da131f8..ef09a9dc6131 100644
--- a/runtime/kusama/src/tests.rs
+++ b/runtime/kusama/src/tests.rs
@@ -137,40 +137,6 @@ fn nominator_limit() {
 	println!("can support {} nominators to yield a weight of {}", active, weight_with(active));
 }
 
-#[test]
-fn compute_inflation_should_give_sensible_results() {
-	assert_eq!(
-		pallet_staking_reward_fn::compute_inflation(
-			Perquintill::from_percent(75),
-			Perquintill::from_percent(75),
-			Perquintill::from_percent(5),
-		),
-		Perquintill::one()
-	);
-	assert_eq!(
-		pallet_staking_reward_fn::compute_inflation(
-			Perquintill::from_percent(50),
-			Perquintill::from_percent(75),
-			Perquintill::from_percent(5),
-		),
-		Perquintill::from_rational(2u64, 3u64)
-	);
-	assert_eq!(
-		pallet_staking_reward_fn::compute_inflation(
-			Perquintill::from_percent(80),
-			Perquintill::from_percent(75),
-			Perquintill::from_percent(5),
-		),
-		Perquintill::from_rational(1u64, 2u64)
-	);
-}
-
-#[test]
-fn era_payout_should_give_sensible_results() {
-	assert_eq!(era_payout(75, 100, Perquintill::from_percent(10), Perquintill::one(), 0,), (10, 0));
-	assert_eq!(era_payout(80, 100, Perquintill::from_percent(10), Perquintill::one(), 0,), (6, 4));
-}
-
 #[test]
 fn call_size() {
 	RuntimeCall::assert_size_under(230);
diff --git a/runtime/polkadot/src/lib.rs b/runtime/polkadot/src/lib.rs
index 5adf4e11e67f..0f71a37f425f 100644
--- a/runtime/polkadot/src/lib.rs
+++ b/runtime/polkadot/src/lib.rs
@@ -58,6 +58,7 @@ use primitives::v2::{
 	CoreState, GroupRotationInfo, Hash, Id as ParaId, InboundDownwardMessage, InboundHrmpMessage,
 	Moment, Nonce, OccupiedCoreAssumption, PersistedValidationData, ScrapedOnChainVotes,
 	SessionInfo, Signature, ValidationCode, ValidationCodeHash, ValidatorId, ValidatorIndex,
+	LOWEST_PUBLIC_ID,
 };
 use sp_core::OpaqueMetadata;
 use sp_mmr_primitives as mmr;
@@ -405,6 +406,9 @@ parameter_types! {
 	/// ... and all of the validators as electable targets. Whilst this is the case, we cannot and
 	/// shall not increase the size of the validator intentions.
 	pub const MaxElectableTargets: u16 = u16::MAX;
+	/// Setup election pallet to support maximum winners upto 1200. This will mean Staking Pallet
+	/// cannot have active validators higher than this count.
+	pub const MaxActiveValidators: u32 = 1200;
 }
 
 generate_solution_type!(
@@ -423,6 +427,9 @@ impl onchain::Config for OnChainSeqPhragmen {
 	type Solver = SequentialPhragmen<AccountId, runtime_common::elections::OnChainAccuracy>;
 	type DataProvider = Staking;
 	type WeightInfo = weights::frame_election_provider_support::WeightInfo<Runtime>;
+	type MaxWinners = MaxActiveValidators;
+	type VotersBound = MaxElectingVoters;
+	type TargetsBound = MaxElectableTargets;
 }
 
 impl pallet_election_provider_multi_phase::MinerConfig for Runtime {
@@ -470,10 +477,15 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type MinerTxPriority = NposSolutionPriority;
 	type DataProvider = Staking;
 	#[cfg(feature = "fast-runtime")]
-	type Fallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	#[cfg(not(feature = "fast-runtime"))]
-	type Fallback = pallet_election_provider_multi_phase::NoFallback<Self>;
-	type GovernanceFallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = frame_election_provider_support::NoElection<(
+		AccountId,
+		BlockNumber,
+		Staking,
+		MaxActiveValidators,
+	)>;
+	type GovernanceFallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type Solver = SequentialPhragmen<
 		AccountId,
 		pallet_election_provider_multi_phase::SolutionAccuracyOf<Self>,
@@ -487,6 +499,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type WeightInfo = weights::pallet_election_provider_multi_phase::WeightInfo<Self>;
 	type MaxElectingVoters = MaxElectingVoters;
 	type MaxElectableTargets = MaxElectableTargets;
+	type MaxWinners = MaxActiveValidators;
 }
 
 parameter_types! {
@@ -525,7 +538,7 @@ parameter_types! {
 	pub const BondingDuration: sp_staking::EraIndex = 28;
 	pub const SlashDeferDuration: sp_staking::EraIndex = 27;
 	pub const RewardCurve: &'static PiecewiseLinear<'static> = &REWARD_CURVE;
-	pub const MaxNominatorRewardedPerValidator: u32 = 256;
+	pub const MaxNominatorRewardedPerValidator: u32 = 512;
 	pub const OffendingValidatorsThreshold: Perbill = Perbill::from_percent(17);
 	// 16
 	pub const MaxNominations: u32 = <NposCompactSolution16 as frame_election_provider_support::NposSolution>::LIMIT as u32;
@@ -536,6 +549,35 @@ type SlashCancelOrigin = EitherOfDiverse<
 	pallet_collective::EnsureProportionAtLeast<AccountId, CouncilCollective, 3, 4>,
 >;
 
+pub struct EraPayout;
+impl pallet_staking::EraPayout<Balance> for EraPayout {
+	fn era_payout(
+		total_staked: Balance,
+		total_issuance: Balance,
+		era_duration_millis: u64,
+	) -> (Balance, Balance) {
+		// all para-ids that are not active.
+		let auctioned_slots = Paras::parachains()
+			.into_iter()
+			// all active para-ids that do not belong to a system or common good chain is the number
+			// of parachains that we should take into account for inflation.
+			.filter(|i| *i >= LOWEST_PUBLIC_ID)
+			.count() as u64;
+
+		const MAX_ANNUAL_INFLATION: Perquintill = Perquintill::from_percent(10);
+		const MILLISECONDS_PER_YEAR: u64 = 1000 * 3600 * 24 * 36525 / 100;
+
+		runtime_common::impls::era_payout(
+			total_staked,
+			// Polkadot has no notion of gilts, the entire issuance is non-guilt.
+			total_issuance,
+			MAX_ANNUAL_INFLATION,
+			Perquintill::from_rational(era_duration_millis, MILLISECONDS_PER_YEAR),
+			auctioned_slots,
+		)
+	}
+}
+
 impl pallet_staking::Config for Runtime {
 	type MaxNominations = MaxNominations;
 	type Currency = Balances;
@@ -552,12 +594,12 @@ impl pallet_staking::Config for Runtime {
 	// A super-majority of the council can cancel the slash.
 	type SlashCancelOrigin = SlashCancelOrigin;
 	type SessionInterface = Self;
-	type EraPayout = pallet_staking::ConvertCurve<RewardCurve>;
+	type EraPayout = EraPayout;
 	type MaxNominatorRewardedPerValidator = MaxNominatorRewardedPerValidator;
 	type OffendingValidatorsThreshold = OffendingValidatorsThreshold;
 	type NextNewSession = Session;
 	type ElectionProvider = ElectionProviderMultiPhase;
-	type GenesisElectionProvider = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type VoterList = VoterList;
 	type TargetList = UseValidatorsMap<Self>;
 	type MaxUnlockingChunks = frame_support::traits::ConstU32<32>;
@@ -570,6 +612,7 @@ impl pallet_staking::Config for Runtime {
 impl pallet_fast_unstake::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type Currency = Balances;
+	type BatchSize = frame_support::traits::ConstU32<64>;
 	type Deposit = frame_support::traits::ConstU128<{ UNITS }>;
 	type ControlOrigin = EitherOfDiverse<
 		EnsureRoot<AccountId>,
@@ -1566,6 +1609,7 @@ pub type Executive = frame_executive::Executive<
 		// "Properly migrate weights to v2" <https://github.com/paritytech/polkadot/pull/6091>
 		parachains_configuration::migration::v3::MigrateToV3<Runtime>,
 		pallet_election_provider_multi_phase::migrations::v1::MigrateToV1<Runtime>,
+		pallet_fast_unstake::migrations::v1::MigrateToV1<Runtime>,
 	),
 >;
 
@@ -1804,53 +1848,27 @@ sp_api::impl_runtime_apis! {
 	}
 
 	impl mmr::MmrApi<Block, Hash, BlockNumber> for Runtime {
-		fn generate_proof(_block_number: BlockNumber)
-			-> Result<(mmr::EncodableOpaqueLeaf, mmr::Proof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof(_leaf: mmr::EncodableOpaqueLeaf, _proof: mmr::Proof<Hash>)
-			-> Result<(), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof_stateless(
-			_root: Hash,
-			_leaf: mmr::EncodableOpaqueLeaf,
-			_proof: mmr::Proof<Hash>
-		) -> Result<(), mmr::Error> {
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
 		fn mmr_root() -> Result<Hash, mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn generate_batch_proof(_block_numbers: Vec<BlockNumber>)
-			-> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn generate_historical_batch_proof(
+		fn generate_proof(
 			_block_numbers: Vec<BlockNumber>,
-			_best_known_block_number: BlockNumber,
-		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error> {
+			_best_known_block_number: Option<BlockNumber>,
+		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::Proof<Hash>), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::BatchProof<Hash>)
+		fn verify_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::Proof<Hash>)
 			-> Result<(), mmr::Error>
 		{
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof_stateless(
+		fn verify_proof_stateless(
 			_root: Hash,
 			_leaves: Vec<mmr::EncodableOpaqueLeaf>,
-			_proof: mmr::BatchProof<Hash>
+			_proof: mmr::Proof<Hash>
 		) -> Result<(), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
diff --git a/runtime/rococo/src/lib.rs b/runtime/rococo/src/lib.rs
index b46d9a15469a..a0975d1ba6bc 100644
--- a/runtime/rococo/src/lib.rs
+++ b/runtime/rococo/src/lib.rs
@@ -1691,52 +1691,15 @@ sp_api::impl_runtime_apis! {
 	}
 
 	impl mmr::MmrApi<Block, Hash, BlockNumber> for Runtime {
-		fn generate_proof(block_number: BlockNumber)
-			-> Result<(mmr::EncodableOpaqueLeaf, mmr::Proof<Hash>), mmr::Error>
-		{
-			Mmr::generate_batch_proof(vec![block_number])
-				.and_then(|(leaves, proof)| Ok((
-					mmr::EncodableOpaqueLeaf::from_leaf(&leaves[0]),
-					mmr::BatchProof::into_single_leaf_proof(proof)?
-				)))
-		}
-
-		fn verify_proof(leaf: mmr::EncodableOpaqueLeaf, proof: mmr::Proof<Hash>)
-			-> Result<(), mmr::Error>
-		{
-			pub type MmrLeaf = <<Runtime as pallet_mmr::Config>::LeafData as mmr::LeafDataProvider>::LeafData;
-			let leaf: MmrLeaf = leaf
-				.into_opaque_leaf()
-				.try_decode()
-				.ok_or(mmr::Error::Verify)?;
-			Mmr::verify_leaves(vec![leaf], mmr::Proof::into_batch_proof(proof))
-		}
-
-		fn verify_proof_stateless(
-			root: Hash,
-			leaf: mmr::EncodableOpaqueLeaf,
-			proof: mmr::Proof<Hash>
-		) -> Result<(), mmr::Error> {
-			let node = mmr::DataOrHash::Data(leaf.into_opaque_leaf());
-			pallet_mmr::verify_leaves_proof::<MmrHashing, _>(root, vec![node], mmr::Proof::into_batch_proof(proof))
-		}
-
 		fn mmr_root() -> Result<Hash, mmr::Error> {
 			Ok(Mmr::mmr_root())
 		}
 
-		fn generate_batch_proof(block_numbers: Vec<BlockNumber>)
-			-> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error>
-		{
-			Mmr::generate_batch_proof(block_numbers)
-				.map(|(leaves, proof)| (leaves.into_iter().map(|leaf| mmr::EncodableOpaqueLeaf::from_leaf(&leaf)).collect(), proof))
-		}
-
-		fn generate_historical_batch_proof(
+		fn generate_proof(
 			block_numbers: Vec<BlockNumber>,
-			best_known_block_number: BlockNumber,
-		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error> {
-			Mmr::generate_historical_batch_proof(block_numbers, best_known_block_number).map(
+			best_known_block_number: Option<BlockNumber>,
+		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::Proof<Hash>), mmr::Error> {
+			Mmr::generate_proof(block_numbers, best_known_block_number).map(
 				|(leaves, proof)| {
 					(
 						leaves
@@ -1749,7 +1712,7 @@ sp_api::impl_runtime_apis! {
 			)
 		}
 
-		fn verify_batch_proof(leaves: Vec<mmr::EncodableOpaqueLeaf>, proof: mmr::BatchProof<Hash>)
+		fn verify_proof(leaves: Vec<mmr::EncodableOpaqueLeaf>, proof: mmr::Proof<Hash>)
 			-> Result<(), mmr::Error>
 		{
 			pub type MmrLeaf = <<Runtime as pallet_mmr::Config>::LeafData as mmr::LeafDataProvider>::LeafData;
@@ -1760,10 +1723,10 @@ sp_api::impl_runtime_apis! {
 			Mmr::verify_leaves(leaves, proof)
 		}
 
-		fn verify_batch_proof_stateless(
+		fn verify_proof_stateless(
 			root: Hash,
 			leaves: Vec<mmr::EncodableOpaqueLeaf>,
-			proof: mmr::BatchProof<Hash>
+			proof: mmr::Proof<Hash>
 		) -> Result<(), mmr::Error> {
 			let nodes = leaves.into_iter().map(|leaf|mmr::DataOrHash::Data(leaf.into_opaque_leaf())).collect();
 			pallet_mmr::verify_leaves_proof::<MmrHashing, _>(root, nodes, proof)
diff --git a/runtime/test-runtime/src/lib.rs b/runtime/test-runtime/src/lib.rs
index 7fba0e20d9fe..0210f1ecd8b7 100644
--- a/runtime/test-runtime/src/lib.rs
+++ b/runtime/test-runtime/src/lib.rs
@@ -319,6 +319,9 @@ parameter_types! {
 	pub storage MaxNominatorRewardedPerValidator: u32 = 64;
 	pub storage OffendingValidatorsThreshold: Perbill = Perbill::from_percent(17);
 	pub const MaxAuthorities: u32 = 100_000;
+	pub const OnChainMaxWinners: u32 = u32::MAX;
+	pub const MaxElectingVoters: u32 = u32::MAX;
+	pub const MaxElectableTargets: u16 = u16::MAX;
 }
 
 pub struct OnChainSeqPhragmen;
@@ -327,6 +330,9 @@ impl onchain::Config for OnChainSeqPhragmen {
 	type Solver = SequentialPhragmen<AccountId, runtime_common::elections::OnChainAccuracy>;
 	type DataProvider = Staking;
 	type WeightInfo = ();
+	type MaxWinners = OnChainMaxWinners;
+	type VotersBound = MaxElectingVoters;
+	type TargetsBound = MaxElectableTargets;
 }
 
 impl pallet_staking::Config for Runtime {
@@ -349,8 +355,8 @@ impl pallet_staking::Config for Runtime {
 	type MaxNominatorRewardedPerValidator = MaxNominatorRewardedPerValidator;
 	type OffendingValidatorsThreshold = OffendingValidatorsThreshold;
 	type NextNewSession = Session;
-	type ElectionProvider = onchain::UnboundedExecution<OnChainSeqPhragmen>;
-	type GenesisElectionProvider = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type ElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
+	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	// Use the nominator map to iter voter AND no-ops for all SortedListProvider hooks. The migration
 	// to bags-list is a no-op, but the storage version will be updated.
 	type VoterList = pallet_staking::UseNominatorsAndValidatorsMap<Runtime>;
@@ -920,53 +926,27 @@ sp_api::impl_runtime_apis! {
 	}
 
 	impl mmr::MmrApi<Block, Hash, BlockNumber> for Runtime {
-		fn generate_proof(_block_number: BlockNumber)
-			-> Result<(mmr::EncodableOpaqueLeaf, mmr::Proof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof(_leaf: mmr::EncodableOpaqueLeaf, _proof: mmr::Proof<Hash>)
-			-> Result<(), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof_stateless(
-			_root: Hash,
-			_leaf: mmr::EncodableOpaqueLeaf,
-			_proof: mmr::Proof<Hash>
-		) -> Result<(), mmr::Error> {
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
 		fn mmr_root() -> Result<Hash, mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn generate_batch_proof(_block_numbers: Vec<BlockNumber>)
-			-> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn generate_historical_batch_proof(
+		fn generate_proof(
 			_block_numbers: Vec<BlockNumber>,
-			_best_known_block_number: BlockNumber,
-		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error> {
+			_best_known_block_number: Option<BlockNumber>,
+		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::Proof<Hash>), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::BatchProof<Hash>)
+		fn verify_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::Proof<Hash>)
 			-> Result<(), mmr::Error>
 		{
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof_stateless(
+		fn verify_proof_stateless(
 			_root: Hash,
 			_leaves: Vec<mmr::EncodableOpaqueLeaf>,
-			_proof: mmr::BatchProof<Hash>
+			_proof: mmr::Proof<Hash>
 		) -> Result<(), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
diff --git a/runtime/westend/src/lib.rs b/runtime/westend/src/lib.rs
index fd5e8a1c7f43..a7930ff06ea6 100644
--- a/runtime/westend/src/lib.rs
+++ b/runtime/westend/src/lib.rs
@@ -366,6 +366,9 @@ parameter_types! {
 	/// ... and all of the validators as electable targets. Whilst this is the case, we cannot and
 	/// shall not increase the size of the validator intentions.
 	pub const MaxElectableTargets: u16 = u16::MAX;
+	// Maximum winners that can be chosen as active validators
+	pub const MaxActiveValidators: u32 = 1000;
+
 }
 
 frame_election_provider_support::generate_solution_type!(
@@ -384,6 +387,9 @@ impl onchain::Config for OnChainSeqPhragmen {
 	type Solver = SequentialPhragmen<AccountId, OnChainAccuracy>;
 	type DataProvider = Staking;
 	type WeightInfo = weights::frame_election_provider_support::WeightInfo<Runtime>;
+	type MaxWinners = MaxActiveValidators;
+	type VotersBound = MaxElectingVoters;
+	type TargetsBound = MaxElectableTargets;
 }
 
 impl pallet_election_provider_multi_phase::MinerConfig for Runtime {
@@ -431,10 +437,15 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type MinerTxPriority = NposSolutionPriority;
 	type DataProvider = Staking;
 	#[cfg(any(feature = "fast-runtime", feature = "runtime-benchmarks"))]
-	type Fallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	#[cfg(not(any(feature = "fast-runtime", feature = "runtime-benchmarks")))]
-	type Fallback = pallet_election_provider_multi_phase::NoFallback<Self>;
-	type GovernanceFallback = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type Fallback = frame_election_provider_support::NoElection<(
+		AccountId,
+		BlockNumber,
+		Staking,
+		MaxActiveValidators,
+	)>;
+	type GovernanceFallback = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type Solver = SequentialPhragmen<
 		AccountId,
 		pallet_election_provider_multi_phase::SolutionAccuracyOf<Self>,
@@ -445,6 +456,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 	type WeightInfo = weights::pallet_election_provider_multi_phase::WeightInfo<Self>;
 	type MaxElectingVoters = MaxElectingVoters;
 	type MaxElectableTargets = MaxElectableTargets;
+	type MaxWinners = MaxActiveValidators;
 }
 
 parameter_types! {
@@ -505,7 +517,7 @@ impl pallet_staking::Config for Runtime {
 	type OffendingValidatorsThreshold = OffendingValidatorsThreshold;
 	type NextNewSession = Session;
 	type ElectionProvider = ElectionProviderMultiPhase;
-	type GenesisElectionProvider = onchain::UnboundedExecution<OnChainSeqPhragmen>;
+	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
 	type VoterList = VoterList;
 	type TargetList = UseValidatorsMap<Self>;
 	type MaxUnlockingChunks = frame_support::traits::ConstU32<32>;
@@ -518,6 +530,7 @@ impl pallet_staking::Config for Runtime {
 impl pallet_fast_unstake::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type Currency = Balances;
+	type BatchSize = frame_support::traits::ConstU32<64>;
 	type Deposit = frame_support::traits::ConstU128<{ UNITS }>;
 	type ControlOrigin = EnsureRoot<AccountId>;
 	type WeightInfo = weights::pallet_fast_unstake::WeightInfo<Runtime>;
@@ -1217,6 +1230,7 @@ pub type Executive = frame_executive::Executive<
 		// "Properly migrate weights to v2" <https://github.com/paritytech/polkadot/pull/6091>
 		parachains_configuration::migration::v3::MigrateToV3<Runtime>,
 		pallet_election_provider_multi_phase::migrations::v1::MigrateToV1<Runtime>,
+		pallet_fast_unstake::migrations::v1::MigrateToV1<Runtime>,
 	),
 >;
 /// The payload being signed in transactions.
@@ -1444,58 +1458,29 @@ sp_api::impl_runtime_apis! {
 	}
 
 	impl mmr::MmrApi<Block, Hash, BlockNumber> for Runtime {
-		fn generate_proof(_block_number: BlockNumber)
-			-> Result<(mmr::EncodableOpaqueLeaf, mmr::Proof<Hash>), mmr::Error>
-		{
-
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof(_leaf: mmr::EncodableOpaqueLeaf, _proof: mmr::Proof<Hash>)
-			-> Result<(), mmr::Error>
-		{
-
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn verify_proof_stateless(
-			_root: Hash,
-			_leaf: mmr::EncodableOpaqueLeaf,
-			_proof: mmr::Proof<Hash>
-		) -> Result<(), mmr::Error> {
-
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
 		fn mmr_root() -> Result<Hash, mmr::Error> {
 
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn generate_batch_proof(_block_numbers: Vec<BlockNumber>)
-			-> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error>
-		{
-			Err(mmr::Error::PalletNotIncluded)
-		}
-
-		fn generate_historical_batch_proof(
+		fn generate_proof(
 			_block_numbers: Vec<BlockNumber>,
-			_best_known_block_number: BlockNumber,
-		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::BatchProof<Hash>), mmr::Error> {
+			_best_known_block_number: Option<BlockNumber>,
+		) -> Result<(Vec<mmr::EncodableOpaqueLeaf>, mmr::Proof<Hash>), mmr::Error> {
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::BatchProof<Hash>)
+		fn verify_proof(_leaves: Vec<mmr::EncodableOpaqueLeaf>, _proof: mmr::Proof<Hash>)
 			-> Result<(), mmr::Error>
 		{
 
 			Err(mmr::Error::PalletNotIncluded)
 		}
 
-		fn verify_batch_proof_stateless(
+		fn verify_proof_stateless(
 			_root: Hash,
 			_leaves: Vec<mmr::EncodableOpaqueLeaf>,
-			_proof: mmr::BatchProof<Hash>
+			_proof: mmr::Proof<Hash>
 		) -> Result<(), mmr::Error> {
 
 			Err(mmr::Error::PalletNotIncluded)
diff --git a/scripts/ci/gitlab/pipeline/build.yml b/scripts/ci/gitlab/pipeline/build.yml
index 791b01c2b632..c6fe5916c3b6 100644
--- a/scripts/ci/gitlab/pipeline/build.yml
+++ b/scripts/ci/gitlab/pipeline/build.yml
@@ -170,7 +170,7 @@ build-implementers-guide:
     - .collect-artifacts-short
   script:
     - apt-get -y update; apt-get install -y graphviz
-    - cargo install mdbook mdbook-mermaid mdbook-linkcheck mdbook-graphviz
+    - cargo install mdbook mdbook-mermaid mdbook-linkcheck mdbook-graphviz mdbook-last-changed
     - mdbook build ./roadmap/implementers-guide
     - mkdir -p artifacts
     - mv roadmap/implementers-guide/book artifacts/
diff --git a/utils/staking-miner/src/emergency_solution.rs b/utils/staking-miner/src/emergency_solution.rs
index cbf86af4c1d0..fdb3a47a270d 100644
--- a/utils/staking-miner/src/emergency_solution.rs
+++ b/utils/staking-miner/src/emergency_solution.rs
@@ -36,21 +36,23 @@ macro_rules! emergency_solution_cmd_for { ($runtime:ident) => { paste::paste! {
 
 			log::info!(target: LOG_TARGET, "mined solution with {:?}", &raw_solution.score);
 
-			let mut ready_solution = EPM::Pallet::<Runtime>::feasibility_check(raw_solution, EPM::ElectionCompute::Signed)?;
-
+			let ready_solution = EPM::Pallet::<Runtime>::feasibility_check(raw_solution, EPM::ElectionCompute::Signed)?;
+			let encoded_size = ready_solution.encoded_size();
+			let score = ready_solution.score;
+			let mut supports = ready_solution.supports.into_inner();
 			// maybe truncate.
 			if let Some(take) = config.take {
-				log::info!(target: LOG_TARGET, "truncating {} winners to {}", ready_solution.supports.len(), take);
-				ready_solution.supports.sort_unstable_by_key(|(_, s)| s.total);
-				ready_solution.supports.truncate(take);
+				log::info!(target: LOG_TARGET, "truncating {} winners to {}", supports.len(), take);
+				supports.sort_unstable_by_key(|(_, s)| s.total);
+				supports.truncate(take);
 			}
 
 			// write to file and stdout.
-			let encoded_support = ready_solution.supports.encode();
+			let encoded_support = supports.encode();
 			let mut supports_file = std::fs::File::create("solution.supports.bin")?;
 			supports_file.write_all(&encoded_support)?;
 
-			log::info!(target: LOG_TARGET, "ReadySolution: size {:?} / score = {:?}", ready_solution.encoded_size(), ready_solution.score);
+			log::info!(target: LOG_TARGET, "ReadySolution: size {:?} / score = {:?}", encoded_size, score);
 			log::trace!(target: LOG_TARGET, "Supports: {}", sp_core::hexdisplay::HexDisplay::from(&encoded_support));
 
 			Ok(())
diff --git a/utils/staking-miner/src/main.rs b/utils/staking-miner/src/main.rs
index 6e5b53423548..8c134874f297 100644
--- a/utils/staking-miner/src/main.rs
+++ b/utils/staking-miner/src/main.rs
@@ -253,7 +253,6 @@ enum Error<T: EPM::Config> {
 	AlreadySubmitted,
 	VersionMismatch,
 	StrategyNotSatisfied,
-	QueueFull,
 	Other(String),
 }
 
diff --git a/utils/staking-miner/src/monitor.rs b/utils/staking-miner/src/monitor.rs
index 0780ef881fce..bfc075668e66 100644
--- a/utils/staking-miner/src/monitor.rs
+++ b/utils/staking-miner/src/monitor.rs
@@ -120,9 +120,8 @@ async fn ensure_strategy_met<T: EPM::Config, B: BlockT>(
 		.map_err::<Error<T>, _>(Into::into)?
 		.unwrap_or_default();
 
-	// we check the queue here as well. Could be checked elsewhere.
-	if indices.len() as u32 >= max_submissions {
-		return Err(Error::<T>::QueueFull)
+	if indices.len() >= max_submissions as usize {
+		log::debug!(target: LOG_TARGET, "The submissions queue is full");
 	}
 
 	// default score is all zeros, any score is better than it.
diff --git a/xcm/xcm-executor/integration-tests/src/lib.rs b/xcm/xcm-executor/integration-tests/src/lib.rs
index 821987531aa0..f038e45d3edc 100644
--- a/xcm/xcm-executor/integration-tests/src/lib.rs
+++ b/xcm/xcm-executor/integration-tests/src/lib.rs
@@ -60,7 +60,7 @@ fn basic_buy_fees_message_executes() {
 	futures::executor::block_on(client.import(sp_consensus::BlockOrigin::Own, block))
 		.expect("imports the block");
 
-	client.state_at(&block_hash).expect("state should exist").inspect_state(|| {
+	client.state_at(block_hash).expect("state should exist").inspect_state(|| {
 		assert!(polkadot_test_runtime::System::events().iter().any(|r| matches!(
 			r.event,
 			polkadot_test_runtime::RuntimeEvent::Xcm(pallet_xcm::Event::Attempted(
@@ -101,7 +101,7 @@ fn query_response_fires() {
 		.expect("imports the block");
 
 	let mut query_id = None;
-	client.state_at(&block_hash).expect("state should exist").inspect_state(|| {
+	client.state_at(block_hash).expect("state should exist").inspect_state(|| {
 		for r in polkadot_test_runtime::System::events().iter() {
 			match r.event {
 				TestNotifier(QueryPrepared(q)) => query_id = Some(q),
@@ -136,7 +136,7 @@ fn query_response_fires() {
 	futures::executor::block_on(client.import(sp_consensus::BlockOrigin::Own, block))
 		.expect("imports the block");
 
-	client.state_at(&block_hash).expect("state should exist").inspect_state(|| {
+	client.state_at(block_hash).expect("state should exist").inspect_state(|| {
 		assert!(polkadot_test_runtime::System::events().iter().any(|r| matches!(
 			r.event,
 			polkadot_test_runtime::RuntimeEvent::Xcm(pallet_xcm::Event::ResponseReady(
@@ -184,7 +184,7 @@ fn query_response_elicits_handler() {
 		.expect("imports the block");
 
 	let mut query_id = None;
-	client.state_at(&block_hash).expect("state should exist").inspect_state(|| {
+	client.state_at(block_hash).expect("state should exist").inspect_state(|| {
 		for r in polkadot_test_runtime::System::events().iter() {
 			match r.event {
 				TestNotifier(NotifyQueryPrepared(q)) => query_id = Some(q),
@@ -218,7 +218,7 @@ fn query_response_elicits_handler() {
 	futures::executor::block_on(client.import(sp_consensus::BlockOrigin::Own, block))
 		.expect("imports the block");
 
-	client.state_at(&block_hash).expect("state should exist").inspect_state(|| {
+	client.state_at(block_hash).expect("state should exist").inspect_state(|| {
 		assert!(polkadot_test_runtime::System::events().iter().any(|r| matches!(
 			r.event,
 			TestNotifier(ResponseReceived(