polkadot-sdk

Profiling polkadot-sdk incremental builds

We profile https://github.com/paritytech/polkadot-sdk, the code behind the Polkadot blockchain and core of all Substrate-based chains.w

Results

Our modded compiler is 35% faster than the default compiler. We shrank incremental build time from 30 seconds to 19 seconds. Full timings reports, and an analysis/report are attached.

• Analysis
• Full timings report for default compiler
• Full timings report for modded compiler

Procedure

'Default' (nightly Feb 29) compiler

# Full cargo check
polkadot-sdk/polkadot$ SKIP_WASM_BUILD=1 RUSTFLAGS="-C linker=/usr/bin/clang -Zself-profile -Zself-profile-events=default,args -Zthreads=8 --cfg tokio_unstable" cargo check --target-dir target-nightly --timings
# Simulate a code change
polkadot-sdk/polkadot$ touch ../substrate/primitives/weights/src/lib.rs
# Incremental cargo check
polkadot-sdk/polkadot$ SKIP_WASM_BUILD=1 RUSTFLAGS="-C linker=/usr/bin/clang -Zself-profile -Zself-profile-events=default,args -Zthreads=8 --cfg tokio_unstable" cargo check --target-dir target-nightly --timings

'Modded' custom compiler

# Full cargo check
polkadot-sdk/polkadot$ SKIP_WASM_BUILD=1 RUSTFLAGS="-C linker=/usr/bin/clang -Zself-profile -Zself-profile-events=default,args -Zthreads=8 --cfg tokio_unstable" cargo +kaprust check --target-dir target-kap --timings
# Simulate a code change
polkadot-sdk/polkadot$ touch ../substrate/primitives/weights/src/lib.rs
# Incremental cargo check
polkadot-sdk/polkadot$ SKIP_WASM_BUILD=1 RUSTFLAGS="-C linker=/usr/bin/clang -Zself-profile -Zself-profile-events=default,args -Zthreads=8 --cfg tokio_unstable" cargo +kaprust check --target-dir target-kap --timings