RE: Usecases for the per-task latency-nice attribute

[David Laight]

From: Tim Chen
> Sent: 18 September 2019 18:16
...
> Some users are running machine learning batch tasks with AVX512, and have observed
> that these tasks affect the tasks needing a fast response.  They have to
> rely on manual CPU affinity to separate these tasks.  With appropriate
> latency hint on task, the scheduler can be taught to separate them.

Will (or can) the scheduler pre-empt a low priority process that is spinning
in userspace in order to allow a high priority (or low latency) process run
on that cpu?

My suspicion is that the process switch can't happen until (at least) the
next hardware interrupt - and possibly only a timer tick into the scheduler.

	David

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