fix: don't run nested ProcessPoolExecutors#1008
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bhearsum merged 1 commit intoJul 17, 2026
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This is kindof a regression from the introduction of the ProcessPoolExecutor for taskgraph generation. It's not _necessarily_ wrong or broken to nest these...but in graphs where memory usage is high during generation it can sometimes cause OOMs. There's really no advantage to using two levels of multiprocessing, so we should avoid doing so.
jcristau
approved these changes
Jul 17, 2026
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This is kindof a regression from the introduction of the ProcessPoolExecutor for taskgraph generation. It's not necessarily wrong or broken to nest these...but in graphs where memory usage is high during generation it can sometimes cause OOMs. There's really no advantage to using two levels of multiprocessing, so we should avoid doing so.