public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jakob Oestergaard <jakob@unthought.net>
To: William Lee Irwin III <wli@holomorphy.com>,
	Phy Prabab <phyprabab@yahoo.com>,
	linux-kernel@vger.kernel.org
Subject: Re: Help understanding slow down
Date: Mon, 24 May 2004 03:25:53 +0200	[thread overview]
Message-ID: <20040524012553.GG30687@unthought.net> (raw)
In-Reply-To: <20040524010455.GJ1833@holomorphy.com>

On Sun, May 23, 2004 at 06:04:55PM -0700, William Lee Irwin III wrote:
> On Sun, May 23, 2004 at 05:57:51PM -0700, Phy Prabab wrote:
> > Just for more clarification, here is a perfect
> > example:
> > 2.6.7-p1:
> > 24.86user 51.77system 2:58.87elapsed 42%CPU
> > (0avgtext+0avgdata 0maxresident)k
> > 0inputs+0outputs (13major+7591686minor)pagefaults
> > 0swaps
> > 2.4.21:
> > 28.68user 34.98system 1:12.34elapsed 87%CPU
> > (0avgtext+0avgdata 0maxresident)k
> > 0inputs+0outputs (5691267major+1130523minor)pagefaults
> > 0swaps
> 
> Thanks. This reveals that the performance regression is system time.

Eh, not if I read the numbers right:

2.6.7-p1: 24.86user 51.77system 2:58.87elapsed 42%CPU

24.86 + 51.77 = 76.63 seconds on CPU, 102.24 seconds of waiting

2.4.21: 28.68user 34.98system 1:12.34elapsed 87%CPU

28.68 + 34.98 = 63.66 seconds on CPU, 8.68 seconds of waiting

So, 2.6.7-p1 spends 16.79 seconds more in the kernel as you observed,
but it spends 93.56 seconds more waiting for I/O (or whatever).

Unless I'm totally missing something, the wait seems to be the
regression.

 / jakob


  reply	other threads:[~2004-05-24  1:25 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-05-24  0:32 Help understanding slow down Phy Prabab
2004-05-24  0:57 ` Phy Prabab
2004-05-24  1:04   ` William Lee Irwin III
2004-05-24  1:25     ` Jakob Oestergaard [this message]
2004-05-24  1:28       ` William Lee Irwin III
2004-05-24  1:51         ` Phy Prabab
2004-05-24  2:42           ` Nick Piggin
2004-05-24  2:43           ` Andrew Morton
2004-05-24  6:23             ` Phy Prabab
2004-05-24  6:27               ` William Lee Irwin III
2004-05-24  6:39                 ` Phy Prabab
2004-05-24  7:21                   ` Phy Prabab
2004-05-24  7:44                     ` Nick Piggin
2004-05-24  7:50                       ` Phy Prabab
2004-05-24  7:59                         ` Nick Piggin
2004-05-24 10:43                           ` Jakob Oestergaard
2004-05-24 14:13                     ` Martin J. Bligh
2004-05-24  7:53                   ` Andrew Morton
2004-05-24  8:00                     ` Phy Prabab
2004-05-25 10:32                     ` Ingo Molnar
2004-05-25  9:29                       ` Andrew Morton
2004-05-25 11:42                         ` Ingo Molnar
2004-05-25  9:58                           ` Andrew Morton
2004-05-25 12:25                             ` Ingo Molnar
2004-05-24  6:33   ` Paul Rolland
2004-05-24 17:28     ` Roger Luethi
  -- strict thread matches above, loose matches on Subject: below --
2004-05-24  1:37 Robert M. Stockmann
2004-05-24  1:50 ` Phy Prabab
2004-05-24  3:31 ` Robert M. Stockmann
2004-05-24  6:14   ` Phy Prabab
2004-05-24 18:36     ` Robert M. Stockmann

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=20040524012553.GG30687@unthought.net \
    --to=jakob@unthought.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=phyprabab@yahoo.com \
    --cc=wli@holomorphy.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox