From: Nick Piggin <piggin@cyberone.com.au>
To: Linus Torvalds <torvalds@osdl.org>
Cc: Andrew Morton <akpm@osdl.org>,
linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: lmbench context switch regression
Date: Thu, 06 Nov 2003 10:16:20 +1100 [thread overview]
Message-ID: <3FA984C4.1030504@cyberone.com.au> (raw)
In-Reply-To: <3FA8ECF0.8020800@cyberone.com.au>
Nick Piggin wrote:
> Hi,
> I'm seeing quite a large context switch speed regression as reported
> by lmbench when I patched from test9 to test9-mm2.
>
> The obvious thing I can see from the patch is the PF_DEAD
> finish_task_switch
> change. I don't have time to investigate further tonight though.
>
> lmbench two 0 sized processes context switch times go from around
> 1.80us to
> 2.60us on my PIII 650 (UP).
The regression is smaller when going from test9 to test9-bk. About .2us
(10%).
It does not go away when reverting the PF_DEAD change. Maybe its just lucky
alignment?
prev parent reply other threads:[~2003-11-05 23:20 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-05 12:28 lmbench context switch regression Nick Piggin
2003-11-05 23:16 ` Nick Piggin [this message]
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=3FA984C4.1030504@cyberone.com.au \
--to=piggin@cyberone.com.au \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@osdl.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.