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From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Josef Bacik <jbacik@fb.com>
Cc: riel@redhat.com, mingo@redhat.com, peterz@infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE
Date: Thu, 28 May 2015 17:25:37 +0530	[thread overview]
Message-ID: <20150528115537.GA25636@linux.vnet.ibm.com> (raw)
In-Reply-To: <1432761736-22093-1-git-send-email-jbacik@fb.com>

> 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


      parent reply	other threads:[~2015-05-28 11:55 UTC|newest]

Thread overview: 73+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-27 21:22 [PATCH RESEND] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE Josef Bacik
2015-05-28  3:46 ` Mike Galbraith
2015-05-28  9:49   ` Morten Rasmussen
2015-05-28 10:57     ` Mike Galbraith
2015-05-28 11:48       ` Morten Rasmussen
2015-05-28 11:49         ` Mike Galbraith
2015-05-28 10:21 ` Peter Zijlstra
2015-05-28 11:05   ` Peter Zijlstra
2015-05-28 14:27     ` Josef Bacik
2015-05-29 21:03     ` Josef Bacik
2015-05-30  3:55       ` Mike Galbraith
2015-06-01 19:38       ` Josef Bacik
2015-06-01 20:42         ` Peter Zijlstra
2015-06-01 21:03           ` Josef Bacik
2015-06-02 17:12           ` Josef Bacik
2015-06-03 14:12             ` Rik van Riel
2015-06-03 14:24               ` Peter Zijlstra
2015-06-03 14:49                 ` Josef Bacik
2015-06-03 15:30                 ` Mike Galbraith
2015-06-03 15:57                   ` Josef Bacik
2015-06-03 16:53                     ` Mike Galbraith
2015-06-03 17:16                       ` Josef Bacik
2015-06-03 17:43                         ` Mike Galbraith
2015-06-03 20:34                           ` Josef Bacik
2015-06-04  4:52                             ` Mike Galbraith
2015-06-01 22:15         ` Rik van Riel
2015-06-11 20:33     ` Josef Bacik
2015-06-12  3:42       ` Rik van Riel
2015-06-12  5:35     ` Mike Galbraith
2015-06-17 18:06       ` Josef Bacik
2015-06-18  0:55         ` Mike Galbraith
2015-06-18  3:46           ` Josef Bacik
2015-06-18  4:12             ` Mike Galbraith
2015-07-02 17:44               ` Josef Bacik
2015-07-03  6:40                 ` Mike Galbraith
2015-07-03  9:29                   ` Mike Galbraith
2015-07-04 15:57                   ` Mike Galbraith
2015-07-05  7:17                     ` Mike Galbraith
2015-07-06  5:13                       ` Mike Galbraith
2015-07-06 14:34                         ` Josef Bacik
2015-07-06 18:36                           ` Mike Galbraith
2015-07-06 19:41                             ` Josef Bacik
2015-07-07  4:01                               ` Mike Galbraith
2015-07-07  9:43                                 ` [patch] " Mike Galbraith
2015-07-07 13:40                                   ` Josef Bacik
2015-07-07 15:24                                     ` Mike Galbraith
2015-07-07 17:06                                   ` Josef Bacik
2015-07-08  6:13                                     ` [patch] sched: beef up wake_wide() Mike Galbraith
2015-07-09 13:26                                       ` Peter Zijlstra
2015-07-09 14:07                                         ` Mike Galbraith
2015-07-09 14:46                                           ` Mike Galbraith
2015-07-10  5:19                                         ` Mike Galbraith
2015-07-10 13:41                                           ` Josef Bacik
2015-07-10 20:59                                           ` Josef Bacik
2015-07-11  3:11                                             ` Mike Galbraith
2015-07-13 13:53                                               ` Josef Bacik
2015-07-14 11:19                                               ` Peter Zijlstra
2015-07-14 13:49                                                 ` Mike Galbraith
2015-07-14 14:07                                                   ` Peter Zijlstra
2015-07-14 14:17                                                     ` Mike Galbraith
2015-07-14 15:04                                                       ` Peter Zijlstra
2015-07-14 15:39                                                         ` Mike Galbraith
2015-07-14 16:01                                                           ` Josef Bacik
2015-07-14 17:59                                                             ` Mike Galbraith
2015-07-15 17:11                                                               ` Josef Bacik
2015-08-03 17:07                                                           ` [tip:sched/core] sched/fair: Beef " tip-bot for Mike Galbraith
2015-05-28 11:16   ` [PATCH RESEND] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE Mike Galbraith
2015-05-28 11:49     ` Ingo Molnar
2015-05-28 12:15       ` Mike Galbraith
2015-05-28 12:19         ` Peter Zijlstra
2015-05-28 12:29           ` Ingo Molnar
2015-05-28 15:22           ` David Ahern
2015-05-28 11:55 ` Srikar Dronamraju [this message]

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