Messages in this thread | | | Date | Thu, 28 May 2015 17:25:37 +0530 | From | Srikar Dronamraju <> | Subject | Re: [PATCH RESEND] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE |
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> At Facebook we have a pretty heavily multi-threaded application that is > sensitive to latency. We have been pulling forward the old SD_WAKE_IDLE code > because it gives us a pretty significant performance gain (like 20%). It turns > out this is because there are cases where the scheduler puts our task on a busy > CPU when there are idle CPU's in the system. We verify this by reading the > cpu_delay_req_avg_us from the scheduler netlink stuff. With our crappy patch we > get much lower numbers vs baseline. >
Was this application run under cpu cgroup. Because we were seeing bursty workloads exhibiting this behaviour esp when run under cpu cgroups.
http://mid.gmane.org/53A11A89.5000602@linux.vnet.ibm.com
-- Thansk and Regards Srikar
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