linux: replace default allocator with jemalloc

.changesets/maint_garypen_jemalloc.md

@@ -0,0 +1,5 @@
+### use jemalloc on linux
+
+Performance testing and flamegraph analysis suggests that jemalloc on linux is about 35% faster than the default allocator.
+
+By [@garypen](https://github.com/garypen) in https://github.com/apollographql/router/pull/2882

Cargo.lock

@@ -378,6 +378,7 @@ dependencies = [
  "test-log",
  "test-span",
  "thiserror",
+ "tikv-jemallocator",
  "tokio",
  "tokio-rustls",
  "tokio-stream",
@@ -5872,6 +5873,26 @@ dependencies = [
  "tower",
 ]
 
+[[package]]
+name = "tikv-jemalloc-sys"
+version = "0.5.3+5.3.0-patched"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a678df20055b43e57ef8cddde41cdfda9a3c1a060b67f4c5836dfb1d78543ba8"
+dependencies = [
+ "cc",
+ "libc",
+]
+
+[[package]]
+name = "tikv-jemallocator"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "20612db8a13a6c06d57ec83953694185a367e16945f66565e8028d2c0bd76979"
+dependencies = [
+ "libc",
+ "tikv-jemalloc-sys",
+]
+
 [[package]]
 name = "time"
 version = "0.3.20"

apollo-router/Cargo.toml

@@ -210,6 +210,7 @@ uname = "0.1.1"
 
 [target.'cfg(unix)'.dependencies]
 uname = "0.1.1"
+tikv-jemallocator = "0.5"
 
 [dev-dependencies]
 ecdsa = { version = "0.15.1", features = ["signing", "pem", "pkcs8"] }
@@ -257,3 +258,4 @@ tonic-build = "0.8.4"
 [[test]]
 name = "integration_tests"
 path = "tests/integration_tests.rs"
+

apollo-router/src/main.rs

@@ -1,4 +1,14 @@
 //! Main entry point for CLI command to start server.
+// Note: We want to use jemalloc on unix, but we don't enable it if dhat-heap is in use because we
+// can only have one global allocator
+#[cfg(target = "unix")]
+#[cfg(not(feature = "dhat-heap"))]
+use tikv_jemallocator::Jemalloc;
+
+#[cfg(target = "unix")]
+#[cfg(not(feature = "dhat-heap"))]
+#[global_allocator]
+static GLOBAL: Jemalloc = Jemalloc;
 
 fn main() {
  match apollo_router::main() {