Use os.sched_getaffinity for parallelism - #9132
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On linux, os.sched_getaffinity(0) reports the number of cores available to the current process. Using it instead of raw os.cpu_count() will have better results when used in conjunction with e.g. `taskset` to limit parallel fuzzing or testing to a subset of the machine's cores.
tlively
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Nice!
We are currently on python 3.10 minimum, and since this code is only used for testing perhaps we can soon update that to 3.13.
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Actually do you want to just copy the emscripten version: |
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Done. Adapted it with some tweaks: inlining |
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| os.path.dirname(os.path.abspath(__file__))) | ||
| default_log_dir = os.path.join(binaryen_root, 'out', 'test') | ||
| cores = os.cpu_count() or 1 | ||
| cores = get_num_cores() or 1 |
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Surely get_num_cores should never return zero / None? Maybe just assert cores instead?
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That's probably fine, but this idiom is apparently a best practice and it seems harmless enough.
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On linux, os.sched_getaffinity(0) reports the number of cores available to the current process. Using it instead of raw os.cpu_count() will have better results when used in conjunction with e.g.
tasksetto limit parallel fuzzing or testing to a subset of the machine's cores.