Build: Limit the numbers of cores used by the build #26059
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Limit to half of the available cores. This seems to give the best performance across machines.
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Prior art #25456 |
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On my MacBook Pro, Core i7 (4 cores, 8 threads), no babel cache present.
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blowery
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[Status] Needs Review
| @@ -72,8 +72,6 @@ const babelLoader = { | |||
| }, | |||
| }; | |||
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| threadLoader.warmup( {}, [ 'babel-loader' ] ); | |||
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Why did you remove this? Or why was it here in the first place?
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it was an attempt to warmup the workers before they would be used. However, it has no apparent speed impact and can make the build hang, waiting for the workers to terminate.
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see docs on prewarming at https://github.com/webpack-contrib/thread-loader
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to repro the hang, add back the prewarm statement and the thread loader require, then configure the thread loader in the server build to use 4 workers. For me, npm run build-server would run, apparently complete, but then hang waiting for something complete.
Removing the warmup killed the hang.
webpack.config.js
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| { | ||
| loader: 'thread-loader', | ||
| options: { | ||
| workers: Math.max( Math.floor( os.cpus().length / 2 ), 1 ), |
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Let's bump the minimum to 2. Even in a hypothetical single core machine, 2 threads would be better than 1 thread (plus the overhead of using thread-loader for a single thread)
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Sure. I was thinking about conditionally ditching the thread-loader based on the number of cores, but defaulting to 2 is fine too.
sirreal
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[Status] Ready to Merge
and removed
[Status] Needs Review
Limit to half of the available cores. This seems to give the best performance across machines.