feat: optimize macOS build times with caching and parallel jobs#148
feat: optimize macOS build times with caching and parallel jobs#148
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- Add sccache-action for compilation caching (up to 50% faster on cache hits) - Cache Node.js source archives to avoid re-downloading - Increase arm64 MAKE_JOB_COUNT from 2 to 3 (matches 3 vCPU on macos-14) - Keep x64 MAKE_JOB_COUNT at 4 (matches 4 vCPU on macos-15-intel) Co-authored-by: robertsLando <11502495+robertsLando@users.noreply.github.com>
- Add yarn cache to setup-node to speed up dependency installation - Create detailed BUILD_OPTIMIZATION.md documenting all changes - Document expected improvements and future optimization opportunities Co-authored-by: robertsLando <11502495+robertsLando@users.noreply.github.com>
.github/workflows/build-macos.yml
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| # Cache Node.js source archives | ||
| - name: Cache Node.js source archive | ||
| uses: actions/cache@v4 | ||
| with: | ||
| path: ~/.pkg-cache/node | ||
| key: node-source-${{ matrix.target-node }}-${{ hashFiles('patches/patches.json') }} | ||
| restore-keys: | | ||
| node-source-${{ matrix.target-node }}- |
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remove caching of nodejs source archive
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Removed Node.js source archive caching. Moved to future optimization opportunities section in the documentation for further investigation. (e95671d)
| // Consider ThinLTO for faster builds | ||
| // args.push('--enable-lto'); // Full LTO | ||
| // Or set via CFLAGS/CXXFLAGS: -flto=thin |
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@faulpeltz any clue if this change could be legit or not?
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thin LTO could help (it basically a faster version of LTO)
but it only works with clang AFAIK
also this is link-time only so not sure how much time this saves
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and what about the sccache then? Could that help? I'm not a C++ expert and I don't like to blindly accept copilot suggestions, I trust you more
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well sccache works by using (compiler env, arch, platform, args, flags, filenames, hashes, ..) as a cache key, if any of that changes it wont do anything, it would only work if rebuilding somehow with the exact same setup, if you change any flag, file content, compiler version, etc. the cache misses
I think it creates a post-action with some stats so its something to try out, but I'm skeptical for our use case
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Thanks for the detailed response! Any other suggestions about how we could speed up macos builds then?
Node.js source archive caching has been moved to future optimization opportunities section as it needs more investigation to ensure it doesn't interfere with the build process. Co-authored-by: robertsLando <11502495+robertsLando@users.noreply.github.com>
macOS builds take 2h (node20), 4h (node22), and 6h (node24) - the main bottleneck for binary releases. This implements compilation caching and optimizes resource utilization.
Changes
Compilation caching with sccache
mozilla-actions/sccache-actionCC: "sccache clang",CXX: "sccache clang++"Optimize parallel compilation
MAKE_JOB_COUNTfrom 2→3 (matches 3 vCPU on macos-14)Yarn dependency caching
cache: 'yarn'insetup-nodeactionExpected Impact
Documentation
Created
docs/BUILD_OPTIMIZATION.mddocumenting:Original prompt
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