Re: CFS scheduler unfairly prefers pinned tasks

From: paul . szabo
Date: Sun Oct 11 2015 - 05:44:10 EST


I wrote:

The Linux CFS scheduler prefers pinned tasks and unfairly
gives more CPU time to tasks that have set CPU affinity.

I believe I have now solved the problem, simply by setting:

for n in /proc/sys/kernel/sched_domain/cpu*/domain0/min_interval; do echo 0 > $n; done
for n in /proc/sys/kernel/sched_domain/cpu*/domain0/max_interval; do echo 1 > $n; done

I am not sure what the domain1 values would be for (that I see exist
on my 4*E5-4627v2 server). So far I do not see any negative effects of
using these (extreme?) settings. (Explanation of what these things are
meant for, or pointers to documentation, would be appreciated.)

---

Thanks for the insightful discussion.

(Scary, isn't it?)

Thanks, Paul

Paul Szabo psz@xxxxxxxxxxxxxxxxx http://www.maths.usyd.edu.au/u/psz/
School of Mathematics and Statistics University of Sydney Australia
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