public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@digeo.com>
To: rwhron@earthlink.net
Cc: linux-kernel@vger.kernel.org
Subject: Re: [BENCHMARK] 12% improvement in fork load from mm3 to mm4
Date: Mon, 9 Jun 2003 15:09:05 -0700	[thread overview]
Message-ID: <20030609150905.7e37bc1f.akpm@digeo.com> (raw)
In-Reply-To: <20030609220255.GA8524@rushmore>

rwhron@earthlink.net wrote:
>
> > autoconf build test creates about 1.2 million processes in
> > 35 minutes.  On quad xeon, there was an improvement of
> > ~ 12% between 2.5.70-mm3 and 2.5.70-mm4.
> > 
> >               Avg of 3 runs
> > 2.5.70-mm3    829.0
> > 2.5.70-mm4    737.9
> 
> profile shows the biggest change is in do_page_fault.

Well that's amusing.  In mm4 I replaced the patch which runs
remap_file_pages() against all prot_exec mappings with a patch which just
prefaults those mappings into pagecache.

The difference _should_ be that in mm3, all pte's are set up at mmap time.
So -mm4 should have more pagefaults, not less.

Something fishy is going on there.  Makes one wonder if remap_file_pages()
is successfully avoiding the minor fault.


  reply	other threads:[~2003-06-09 21:59 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-06-09 22:02 [BENCHMARK] 12% improvement in fork load from mm3 to mm4 rwhron
2003-06-09 22:09 ` Andrew Morton [this message]
  -- strict thread matches above, loose matches on Subject: below --
2003-06-08 22:42 rwhron

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=20030609150905.7e37bc1f.akpm@digeo.com \
    --to=akpm@digeo.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rwhron@earthlink.net \
    /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