Messages in this thread | | | Date | Mon, 10 Jun 2013 10:01:25 +0800 | From | Alex Shi <> | Subject | Re: [patch v8 6/9] sched: compute runnable load avg in cpu_load and cpu_avg_load_per_task |
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On 06/10/2013 09:49 AM, Gu Zheng wrote: > On 06/07/2013 03:20 PM, Alex Shi wrote: > >> > They are the base values in load balance, update them with rq runnable >> > load average, then the load balance will consider runnable load avg >> > naturally. >> > >> > We also try to include the blocked_load_avg as cpu load in balancing, >> > but that cause kbuild performance drop 6% on every Intel machine, and >> > aim7/oltp drop on some of 4 CPU sockets machines. > Hi Alex, > Could you explain me why including the blocked_load_avg causes performance drop ?
Thanks for review!
the 9th patch has few explanation. like, after the only task got into sleep in a CPU, there is only blocked_load_avg left, it looks quite big in short time. that, block it get tasks before sleep, drive task to other cpu in periodic balance. So, it cause clear load imbalance.
-- Thanks Alex
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