Compile instructions

The official polkadot binaries are reasonably optimized but they are not targeting specific CPU architectures. The same is true for the official docker image since they inject the official binary.

Compiling your own binary with optimizations for the architecture of your validator node is not that difficult. The explanation below is adapted from Parity’s github page.

On a modern CPU an optimized compiled binary can have up to 6% better CPU scores relative to the official binary. See here for the detailed results with an Intel i7-12700.

Compiling polkadot requires a fairly recent OS to work out of the box. The following instructions are confirmed to work on Ubuntu 22.04.

One time only: install required libraries and rust

sudo apt install cmake clang lld build-essential git libclang-dev pkg-config libssl-dev
curl https://sh.rustup.rs -sSf | sh
source $HOME/.cargo/env

With each new polkadot release: Update rust

rustup update

Get the source files of the official polkadot release version VER. Beware: The commands below remove the old files!

export VER=0.9.26
mkdir -p ~/optimized_polkadot
cd ~/optimized_polkadot
rm -rf polkadot
git clone --depth 1 --branch v${VER} https://github.com/paritytech/polkadot.git

cd polkadot
./scripts/init.sh
cargo fetch

Choose your optimization options. The options below work well on our test machine (i7-12700). See here for more details and which options you can choose

rustup override set nightly
export RUSTFLAGS="-C target-cpu=native -C codegen=1"
cargo build --release --target=x86_64-unknown-linux-gnu --locked -Z unstable-options

Compiling takes a little while. On a fast machine with NVMe storage, it is about 15 minutes.

From our latest analysis, we have detected better build options that have to be specified as a profile in the Cargo.toml file. Please use our convenient Python script for building.

Benchmark your optimized binary polkadot_opt to make sure it runs OK.

cp target/x86_64-unknown-linux-gnu/release/polkadot ~/optimized_polkadot/polkadot_opt
cd ~/optimized_polkadot
polkadot_opt benchmark machine --disk-duration 30

Optional: compare with the official binary to see if it was worth the trouble.

cd ~/optimized_polkadot/
wget https://github.com/paritytech/polkadot/releases/download/v${VER}/polkadot
chmod +x polkadot
polkadot benchmark machine --disk-duration 30

If you are happy, deploy the optimized binary. With systemd, you can simply replace the official binary with the optimized one and restart the service. For docker, you will need to build your own docker image.

• New polkadot versions can require newer version of system libraries and programs (for example, cmake). Updating your machine with sudo apt update is advisable.