Re: [PATCH 00/23] kbuild: significantly speed up kernel builds
From: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
Date: 2026-09-13 16:27:40
Also in:
linux-arch, linux-efi, linux-kbuild, linux-riscv, lkml, llvm, rust-for-linux
On Fri, Sep 11, 2026 at 11:44:37PM -0700, Nathan Chancellor wrote:
On Fri, Sep 11, 2026 at 12:28:34PM +0100, Lorenzo Stoakes (ARM) wrote:quoted
On Wed, Sep 09, 2026 at 02:58:59PM -0700, Florian Fainelli wrote:quoted
On 9/8/26 13:55, Lorenzo Stoakes (ARM) wrote:quoted
A typical kernel build consists of a frustratingly large amount of time spent stuck in single-threaded bottlenecks. It turns out that there's a lot we can do about this and doing so significantly impacts kernel build times. This series makes allmodconfig builds up to 36% faster, incremental builds up to ~70% faster, and noop builds up to ~90% faster. Builds are faster across the board on every device I tested. Machines used for perf testing: * Threadripper - x86, AMD Threadripper 9980X, 64 cores, 128 threads * EPYC - x86, 2 socket EPYC 9754, 256 cores, 512 threads * M2 - arm64, 2022 M2 macbook pro, 8 cores, 8 threads (4 perf, 4 efficiency)My AMD EPYC 9454P server shows an improvement in the order of 13% using the arm64's defconfig and make -j97. Thanks for doing this!Nice thanks! Good to confirm others are seeing the benefits :)I see similar gains on an 80-core Ampere Altra system 6h 21m 42s -> 5h 31m 15s (-13.22%) and a 32-core AMD system. 3h 38m 55s -> 3h 13m 18s (-11.7%) The build matrices were different between machines but it is good to see similar numbers across different environments.
Nice, yes for sure!
-- Cheers, Nathan
-- Cheers, Lorenzo