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A comment on No nuances, just buggy code (was: related to Spinlock implementation). Parent comment

Re:No nuances, just buggy code (was: related to Spinlock imp... by muststopmyths on Sunday January 05, 2020 @11:56AM (#21962181)
EXACTLY! I wish someone would just explain why the behavior is different. Does linux only sched_yield on the same NUMA node ? (Linus' reply seemed to imply that). Windows will not pin threads unless you set processor affinity, AFAIK, so maybe that's the difference.

There are runnable threads that are not being run. It would be nice to know why.

Tell a person their code is wrong and you may have saved them from one mistake. Tell them why their code is wrong and you will save them from a dozen.

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Re:No nuances, just buggy code (was: related to Spinlock imp... by wyldfire on Sunday January 05, 2020 @12:07PM (#21962255)
> Does linux only sched_yield on the same NUMA node ? (Linus' reply seemed to imply that).

Perhaps Linus' concern is that sched_yield doesn't guarantee any particular behavior, it just happens to be implemented that way now.

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Re:No nuances, just buggy code (was: related to Spinlock imp... by Dylan16807 on Sunday January 05, 2020 @01:11PM (#21962807)
> Does linux only sched_yield on the same NUMA node ?

> There are runnable threads that are not being run. It would be nice to know why.

More extreme. It only applies to the same core, more or less. The original benchmarks are on a one-node CPU, after all.

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