From: Andrew Morton <akpm@zip.com.au>
To: Robert Love <rml@tech9.net>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] low-latency zap_page_range()
Date: Thu, 29 Aug 2002 14:22:12 -0700 [thread overview]
Message-ID: <3D6E9084.820B2608@zip.com.au> (raw)
In-Reply-To: <1030655532.12110.2691.camel@phantasy>
Robert Love wrote:
>
> On Thu, 2002-08-29 at 17:00, Andrew Morton wrote:
>
> > That's an interesting point. page_table_lock is one of those locks
> > which is occasionally held for ages, and frequently held for a short
> > time.
>
> Since latency is a direct function of lock held times in the preemptible
> kernel, and I am seeing disgusting zap_page_range() latencies, the lock
> is held a long time.
>
> So we know it is held forever and a day... but is there contention?
I'm sure there is, but nobody has measured the right workload.
Two CLONE_MM threads, one running mmap()/munmap(), the other trying
to fault in some pages. I'm sure someone has some vital application
which does exactly this. They always do :(
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/
next prev parent reply other threads:[~2002-08-29 21:22 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-08-29 15:31 Robert Love
2002-08-29 20:30 ` Andrew Morton
2002-08-29 20:40 ` Robert Love
2002-08-29 20:46 ` Robert Love
2002-08-29 20:59 ` Andrew Morton
2002-08-29 21:38 ` William Lee Irwin III
2002-08-29 21:00 ` Andrew Morton
2002-08-29 21:12 ` Robert Love
2002-08-29 21:22 ` Andrew Morton [this message]
2002-08-29 21:46 ` Rik van Riel
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=3D6E9084.820B2608@zip.com.au \
--to=akpm@zip.com.au \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=rml@tech9.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