Why does CentOS Linux use cpu/core #1 so much more in a 4-core system?

Posted by ck_ on Server Fault See other posts from Server Fault or by ck_
Published on 2012-11-11T14:47:58Z Indexed on 2012/11/11 17:03 UTC
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cpu

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multi-core

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affinity

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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