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I've been watching top and htop for awhile on a very active server and I am wondering why linux does not automatically use cpu affinity better?

CPU #1 (actually core #1 of 4) is used much more heavily than the others.

Is there a setting similar to what vm.swappiness does for vm swap that forces a preferred affinity pattern?

Should I be using forced affinity settings within mysql/apache/nginx/exim to get better results?

This is on CentOS 2.6.32-279 x86_64 SMP

Thanks for any suggestions.

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If/when you only have enough work to utilize one core, what makes you think it matters which core is used? –  Skaperen Nov 11 '12 at 17:46
I would like to add to @Skaperen 's comment. If you do not have enough work to load multiple cores, it makes sense to do as much as you can on s single core. Both from a cache hit point, as well as with cores which 'turbo' up one or more bins. If your average load if >=2 then please add that to the OP. –  Hennes Nov 11 '12 at 23:45
With all the responses about not enough load, it's still going to respond faster when core #1 is more readily available if it defaults to that. –  ck_ Nov 12 '12 at 3:24

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