All of lore.kernel.org
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@kernel.org>
To: Mike Galbraith <efault@gmx.de>
Cc: Borislav Petkov <bp@alien8.de>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Mel Gorman <mgorman@suse.de>,
	Nikolay Ulyanitsky <lystor@gmail.com>,
	linux-kernel@vger.kernel.org,
	Andreas Herrmann <andreas.herrmann3@amd.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Suresh Siddha <suresh.b.siddha@intel.com>
Subject: Re: 20% performance drop on PostgreSQL 9.2 from kernel 3.5.3 to 3.6-rc5 on AMD chipsets - bisected
Date: Thu, 27 Sep 2012 08:41:42 +0200	[thread overview]
Message-ID: <20120927064142.GB5996@gmail.com> (raw)
In-Reply-To: <1348727665.7059.160.camel@marge.simpson.net>


* Mike Galbraith <efault@gmx.de> wrote:

> > Just to confirm, if you turn off all preemption via a hack 
> > (basically if you turn SCHED_OTHER into SCHED_BATCH), does 
> > psql perform and scale much better, with the quality of 
> > sibling selection and spreading of processes only being a 
> > secondary effect?
> 
> That has always been the case here.  Preemption dominates.

Yes, so we get the best psql performance if we allow the central 
proxy process to dominate a single CPU (IIRC it can easily go up 
to 100% CPU utilization on that CPU - it is what determines max 
psql throughput), and not let any worker run there much, right?

> Others should play with it too, and let their boxen speak.

Do you have an easy-to-apply hack patch by chance that has the 
effect of turning off all such preemption, which people could 
try?

Thanks,

	Ingo

  reply	other threads:[~2012-09-27  6:41 UTC|newest]

Thread overview: 115+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-14  7:47 20% performance drop on PostgreSQL 9.2 from kernel 3.5.3 to 3.6-rc5 on AMD chipsets Nikolay Ulyanitsky
2012-09-14 18:40 ` Borislav Petkov
2012-09-14 18:51   ` Borislav Petkov
2012-09-14 21:27 ` 20% performance drop on PostgreSQL 9.2 from kernel 3.5.3 to 3.6-rc5 on AMD chipsets - bisected Borislav Petkov
2012-09-14 21:40   ` Peter Zijlstra
2012-09-14 21:44     ` Linus Torvalds
2012-09-14 21:56       ` Peter Zijlstra
2012-09-14 21:59         ` Peter Zijlstra
2012-09-15  3:57           ` Mike Galbraith
2012-09-14 22:01         ` Linus Torvalds
2012-09-14 22:10           ` Peter Zijlstra
2012-09-14 22:20             ` Linus Torvalds
2012-09-14 22:14           ` Borislav Petkov
2012-09-14 21:45     ` Borislav Petkov
2012-09-14 21:42   ` Linus Torvalds
2012-09-15  3:33     ` Mike Galbraith
2012-09-15 16:16       ` Andi Kleen
2012-09-15 16:36         ` Mike Galbraith
2012-09-15 17:08           ` richard -rw- weinberger
2012-09-16  4:48             ` Mike Galbraith
2012-09-15 21:32           ` Alan Cox
2012-09-16  4:35             ` Mike Galbraith
2012-09-16 19:57               ` Linus Torvalds
2012-09-17  8:08                 ` Mike Galbraith
2012-09-17 10:07                   ` Ingo Molnar
2012-09-17 10:47                     ` Mike Galbraith
2012-09-17 14:39                     ` Andi Kleen
2012-09-19 12:35               ` Mike Galbraith
2012-09-19 14:54                 ` Ingo Molnar
2012-09-19 15:23                   ` Mike Galbraith
2012-09-24 15:00     ` Mel Gorman
2012-09-24 15:23       ` Nikolay Ulyanitsky
2012-09-24 15:53         ` Borislav Petkov
2012-09-24 15:30       ` Peter Zijlstra
2012-09-24 15:51         ` Mike Galbraith
2012-09-24 15:52         ` Linus Torvalds
2012-09-24 16:07           ` Peter Zijlstra
2012-09-24 16:33             ` Linus Torvalds
2012-09-24 16:54               ` Peter Zijlstra
2012-09-25 12:10                 ` Hillf Danton
2012-09-24 16:12           ` Peter Zijlstra
2012-09-24 16:30             ` Linus Torvalds
2012-09-24 16:52               ` Borislav Petkov
2012-09-24 16:54               ` Peter Zijlstra
2012-09-24 17:44                 ` Peter Zijlstra
2012-09-25 13:23                   ` Mel Gorman
2012-09-25 14:36                     ` Peter Zijlstra
2012-09-24 18:26                 ` Mike Galbraith
2012-09-24 19:12                   ` Linus Torvalds
2012-09-24 19:20                     ` Borislav Petkov
2012-09-25  1:57                       ` Mike Galbraith
2012-09-25  2:11                         ` Linus Torvalds
2012-09-25  2:49                           ` Mike Galbraith
2012-09-25  3:10                             ` Linus Torvalds
2012-09-25  3:20                               ` Mike Galbraith
2012-09-25  3:32                                 ` Linus Torvalds
2012-09-25  3:43                                   ` Mike Galbraith
2012-09-25 11:58                           ` Peter Zijlstra
2012-09-25 13:17                             ` Borislav Petkov
2012-09-25 17:00                               ` Borislav Petkov
2012-09-25 17:21                                 ` Linus Torvalds
2012-09-25 18:42                                   ` Borislav Petkov
2012-09-25 19:08                                     ` Linus Torvalds
2012-09-26  2:23                                     ` Mike Galbraith
2012-09-26 17:17                                       ` Borislav Petkov
2012-09-26  2:00                                   ` Mike Galbraith
2012-09-26  2:22                                     ` Linus Torvalds
2012-09-26  2:42                                       ` Mike Galbraith
2012-09-26 17:15                                       ` Borislav Petkov
2012-09-26 16:32                                   ` Borislav Petkov
2012-09-26 18:19                                     ` Linus Torvalds
2012-09-26 21:37                                       ` Borislav Petkov
2012-09-27  5:09                                         ` Mike Galbraith
2012-09-27  5:18                                           ` Borislav Petkov
2012-09-27  5:44                                             ` Mike Galbraith
2012-09-27  5:47                                           ` Ingo Molnar
2012-09-27  5:59                                             ` Ingo Molnar
2012-09-27  6:34                                             ` Mike Galbraith
2012-09-27  6:41                                               ` Ingo Molnar [this message]
2012-09-27  6:54                                                 ` Mike Galbraith
2012-09-27  7:10                                                   ` Ingo Molnar
2012-09-27 16:25                                                     ` Borislav Petkov
2012-09-27 17:44                                                     ` Linus Torvalds
2012-09-27 18:05                                                       ` Borislav Petkov
2012-09-27 18:19                                                         ` Linus Torvalds
2012-09-27 18:29                                                           ` Peter Zijlstra
2012-09-27 19:24                                                             ` Borislav Petkov
2012-09-28  3:50                                                               ` Mike Galbraith
2012-09-28 12:30                                                                 ` Borislav Petkov
2012-09-27 19:40                                                             ` Linus Torvalds
2012-09-28  4:13                                                               ` Mike Galbraith
2012-09-28  8:37                                                               ` Peter Zijlstra
2012-09-27  7:17                                         ` david
2012-09-27  7:55                                           ` Mike Galbraith
2012-09-27 10:20                                           ` Borislav Petkov
2012-09-27 13:38                                             ` Mike Galbraith
2012-09-27 16:55                                             ` david
2012-09-27  4:32                                       ` Mike Galbraith
2012-09-27  8:21                                       ` Peter Zijlstra
2012-09-27 16:48                                         ` david
2012-09-27 17:38                                           ` Peter Zijlstra
2012-09-27 17:45                                             ` david
2012-09-27 18:09                                               ` Peter Zijlstra
2012-09-27 18:15                                               ` Linus Torvalds
2012-09-27 18:24                                               ` Borislav Petkov
2012-09-25  1:39                     ` Mike Galbraith
2012-09-25 21:11                     ` Suresh Siddha
2012-09-25  4:16       ` Mike Galbraith
2012-09-15  4:11   ` Mike Galbraith
     [not found]     ` <CA+55aFz1A7HbMYS9o-GTS5Zm=Xx8MUD7cR05GMVo--2E34jcgQ@mail.gmail.com>
2012-09-15  4:42       ` Mike Galbraith
2012-09-15 10:44     ` Borislav Petkov
2012-09-15 14:47       ` Mike Galbraith
2012-09-15 15:18         ` Borislav Petkov
2012-09-15 16:13           ` Mike Galbraith
2012-09-15 19:44             ` Borislav Petkov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20120927064142.GB5996@gmail.com \
    --to=mingo@kernel.org \
    --cc=a.p.zijlstra@chello.nl \
    --cc=akpm@linux-foundation.org \
    --cc=andreas.herrmann3@amd.com \
    --cc=bp@alien8.de \
    --cc=efault@gmx.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lystor@gmail.com \
    --cc=mgorman@suse.de \
    --cc=suresh.b.siddha@intel.com \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.