All the mail mirrored from lore.kernel.org
 help / color / mirror / Atom feed
From: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>, Matthew Wilcox <matthew@wil.cx>,
	LKML <linux-kernel@vger.kernel.org>,
	Alexander Viro <viro@ftp.linux.org.uk>,
	Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: AIM7 40% regression with 2.6.26-rc1
Date: Wed, 07 May 2008 12:46:16 +0800	[thread overview]
Message-ID: <1210135576.3453.51.camel@ymzhang> (raw)
In-Reply-To: <20080506205930.91ec78b6.akpm@linux-foundation.org>


On Tue, 2008-05-06 at 20:59 -0700, Andrew Morton wrote:
> On Wed, 07 May 2008 11:41:52 +0800 "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> wrote:
> 
> > As system idle is more than 50%, so the schedule/schedule_timeout caller is important
> > information.
> > 1) lock_kernel causes most schedule/schedule_timeout;
> > 2) When lock_kernel calls down, then __down, __down calls ___schedule_timeout for
> > lots of times in a loop;
> 
> Really?  Are you sure?  That would imply that we keep on waking up tasks
> which then fail to acquire the lock.  But the code pretty plainly doesn't
> do that.
Yes, totally based on the data.
The data means the calling times among functions. Initially , I just collected the caller
of schedule and schedule_timeout. Then I found most schedule/schedule_timeout are called by
__down which is called down. Then, I changes kernel to collect more functions' calling info.

If comparing the calling times of down, __down and schedule_timeout, we could find
schedule_timeout is called by __down for 222330308, but __down is called only for 153190.

> 
> Odd.
> 
> > 3) Caller of lcok_kernel are sys_fcntl/vfs_ioctl/tty_release/chrdev_open.
> Still :(
Yes. The data has an error difference, but the difference is small. My patch doesn't
use lock to protect data in case it might introduces too much overhead.



  reply	other threads:[~2008-05-07  4:47 UTC|newest]

Thread overview: 140+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-06  5:48 AIM7 40% regression with 2.6.26-rc1 Zhang, Yanmin
2008-05-06 11:18 ` Matthew Wilcox
2008-05-06 11:44 ` Ingo Molnar
2008-05-06 12:09   ` Matthew Wilcox
2008-05-06 16:23     ` Matthew Wilcox
2008-05-06 16:36       ` Linus Torvalds
2008-05-06 16:42         ` Matthew Wilcox
2008-05-06 16:39           ` Alan Cox
2008-05-06 16:51             ` Matthew Wilcox
2008-05-06 16:45               ` Alan Cox
2008-05-06 17:42               ` Linus Torvalds
2008-05-06 20:28           ` Linus Torvalds
2008-05-06 16:44         ` J. Bruce Fields
2008-05-06 17:21       ` Andrew Morton
2008-05-06 17:31         ` Matthew Wilcox
2008-05-06 17:49           ` Ingo Molnar
2008-05-06 18:07             ` Andrew Morton
2008-05-11 11:11               ` Matthew Wilcox
2008-05-06 17:39         ` Ingo Molnar
2008-05-07  6:49           ` Zhang, Yanmin
2008-05-06 17:45         ` Linus Torvalds
2008-05-07 16:38         ` Matthew Wilcox
2008-05-07 16:55           ` Linus Torvalds
2008-05-07 17:08             ` Linus Torvalds
2008-05-07 17:16               ` Andrew Morton
2008-05-07 17:27                 ` Linus Torvalds
2008-05-07 17:22               ` Ingo Molnar
2008-05-07 17:25                 ` Ingo Molnar
2008-05-07 17:31                 ` Linus Torvalds
2008-05-07 17:47                   ` Linus Torvalds
2008-05-07 17:49                   ` Ingo Molnar
2008-05-07 18:02                     ` Linus Torvalds
2008-05-07 18:17                       ` Ingo Molnar
2008-05-07 18:27                         ` Linus Torvalds
2008-05-07 18:43                           ` Ingo Molnar
2008-05-07 19:01                             ` Linus Torvalds
2008-05-07 19:09                               ` Ingo Molnar
2008-05-07 19:24                               ` Matthew Wilcox
2008-05-07 19:44                                 ` Linus Torvalds
2008-05-07 20:00                                   ` Oi. NFS people. Read this Matthew Wilcox
2008-05-07 22:10                                     ` Trond Myklebust
2008-05-09  1:43                                       ` J. Bruce Fields
2008-05-08  3:24       ` AIM7 40% regression with 2.6.26-rc1 Zhang, Yanmin
2008-05-08  3:34         ` Linus Torvalds
2008-05-08  4:37           ` Zhang, Yanmin
2008-05-08 14:58             ` Linus Torvalds
2008-05-07  2:11   ` Zhang, Yanmin
2008-05-07  3:41     ` Zhang, Yanmin
2008-05-07  3:59       ` Andrew Morton
2008-05-07  4:46         ` Zhang, Yanmin [this message]
2008-05-07  6:26       ` Ingo Molnar
2008-05-07  6:28         ` Ingo Molnar
2008-05-07  7:05           ` Zhang, Yanmin
2008-05-07 11:00       ` Andi Kleen
2008-05-07 11:46         ` Matthew Wilcox
2008-05-07 12:21           ` Andi Kleen
2008-05-07 14:36             ` Linus Torvalds
2008-05-07 14:35               ` Alan Cox
2008-05-07 15:00                 ` Linus Torvalds
2008-05-07 15:02                   ` Linus Torvalds
2008-05-07 14:57               ` Andi Kleen
2008-05-07 15:31                 ` Andrew Morton
2008-05-07 16:22                   ` Matthew Wilcox
2008-05-07 15:19               ` Linus Torvalds
2008-05-07 17:14                 ` Ingo Molnar
2008-05-08  2:44                 ` Zhang, Yanmin
2008-05-08  3:29                   ` Linus Torvalds
2008-05-08  4:08                     ` Zhang, Yanmin
2008-05-08  4:17                       ` Linus Torvalds
2008-05-08 12:01                         ` [patch] speed up / fix the new generic semaphore code (fix AIM7 40% regression with 2.6.26-rc1) Ingo Molnar
2008-05-08 12:28                           ` Ingo Molnar
2008-05-08 14:43                             ` Ingo Molnar
2008-05-08 15:10                               ` [git pull] scheduler fixes Ingo Molnar
2008-05-08 15:33                                 ` Adrian Bunk
2008-05-08 15:41                                   ` Ingo Molnar
2008-05-08 19:42                                     ` Adrian Bunk
2008-05-11 11:03                                 ` Matthew Wilcox
2008-05-11 11:14                                   ` Matthew Wilcox
2008-05-11 11:48                                   ` Matthew Wilcox
2008-05-11 12:50                                     ` Ingo Molnar
2008-05-11 12:52                                       ` Ingo Molnar
2008-05-11 13:02                                         ` Matthew Wilcox
2008-05-11 13:26                                           ` Matthew Wilcox
2008-05-11 14:00                                             ` Ingo Molnar
2008-05-11 14:18                                               ` Matthew Wilcox
2008-05-11 14:42                                                 ` Ingo Molnar
2008-05-11 14:48                                                   ` Matthew Wilcox
2008-05-11 15:19                                                     ` Ingo Molnar
2008-05-11 15:29                                                       ` Matthew Wilcox
2008-05-13 14:11                                                         ` Ingo Molnar
2008-05-13 14:21                                                           ` Matthew Wilcox
2008-05-13 14:42                                                             ` Ingo Molnar
2008-05-13 15:28                                                               ` Matthew Wilcox
2008-05-13 17:13                                                                 ` Ingo Molnar
2008-05-13 17:22                                                                   ` Linus Torvalds
2008-05-13 21:05                                                                     ` Ingo Molnar
2008-05-11 13:54                                           ` Ingo Molnar
2008-05-11 14:22                                             ` Matthew Wilcox
2008-05-11 14:32                                               ` Ingo Molnar
2008-05-11 14:46                                                 ` Matthew Wilcox
2008-05-11 16:47                                                 ` Linus Torvalds
2008-05-11 13:01                                   ` Ingo Molnar
2008-05-11 13:06                                     ` Matthew Wilcox
2008-05-11 13:45                                       ` Ingo Molnar
2008-05-11 14:10                                   ` Sven Wegener
2008-05-08 16:02                             ` [patch] speed up / fix the new generic semaphore code (fix AIM7 40% regression with 2.6.26-rc1) Linus Torvalds
2008-05-08 18:30                               ` Linus Torvalds
2008-05-08 20:19                                 ` Ingo Molnar
2008-05-08 20:27                                   ` Linus Torvalds
2008-05-08 21:45                                     ` Ingo Molnar
2008-05-08 22:02                                       ` Ingo Molnar
2008-05-08 22:55                                       ` Linus Torvalds
2008-05-08 23:07                                         ` Linus Torvalds
2008-05-08 23:14                                           ` Linus Torvalds
2008-05-08 23:16                                         ` Alan Cox
2008-05-08 23:33                                           ` Linus Torvalds
2008-05-08 23:27                                             ` Alan Cox
2008-05-09  6:50                                             ` Ingo Molnar
2008-05-09  8:29                                             ` Andi Kleen
2008-05-08 13:20                           ` Matthew Wilcox
2008-05-08 15:01                             ` Ingo Molnar
2008-05-08 13:56                           ` Arjan van de Ven
2008-05-08  6:43                   ` AIM7 40% regression with 2.6.26-rc1 Ingo Molnar
2008-05-08  6:48                     ` Andrew Morton
2008-05-08  7:14                     ` Zhang, Yanmin
2008-05-08  7:39                       ` Ingo Molnar
2008-05-08  8:44                         ` Zhang, Yanmin
2008-05-08  9:21                           ` Ingo Molnar
2008-05-08  9:29                             ` Ingo Molnar
2008-05-08  9:30                             ` Zhang, Yanmin
2008-05-07 16:20               ` Ingo Molnar
2008-05-07 16:35                 ` Linus Torvalds
2008-05-07 17:05                   ` Ingo Molnar
2008-05-07 17:24                     ` Linus Torvalds
2008-05-07 17:36                       ` Ingo Molnar
2008-05-07 17:55                         ` Linus Torvalds
2008-05-07 17:59                           ` Matthew Wilcox
2008-05-07 18:17                             ` Linus Torvalds
2008-05-07 18:49                               ` Ingo Molnar
2008-05-07 13:59         ` Alan Cox

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=1210135576.3453.51.camel@ymzhang \
    --to=yanmin_zhang@linux.intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=matthew@wil.cx \
    --cc=mingo@elte.hu \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@ftp.linux.org.uk \
    /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.