From: "Stephen C. Tweedie" <sct@redhat.com>
To: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Stephen C. Tweedie" <sct@redhat.com>,
Chris Mason <mason@suse.com>,
Daniel Phillips <phillips@bonn-fries.net>,
linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org
Subject: Re: [PATCH] 2.4.x write barriers (updated for ext3)
Date: Mon, 4 Mar 2002 19:55:37 +0000 [thread overview]
Message-ID: <20020304195537.I1444@redhat.com> (raw)
In-Reply-To: <sct@redhat.com> <200203041828.g24ISJo09358@localhost.localdomain>
In-Reply-To: <200203041828.g24ISJo09358@localhost.localdomain>; from James.Bottomley@steeleye.com on Mon, Mar 04, 2002 at 12:28:19PM -0600
Hi,
On Mon, Mar 04, 2002 at 12:28:19PM -0600, James Bottomley wrote:
> There is one remaining curiosity I have, at least about the benchmarks: Since
> the linux elevator and tag queueing perform essentially similar function
> (except that the disk itself has a better notion of ordering because it knows
> its own geometry). Might we get better performance by reducing the number of
> tags we allow the device to use, thus forcing the writes to remain longer in
> the linux elevator?
Possibly, but my gut feeling says no and so do any benchmarks I've
seen regarding queue depths on adaptec controllers (not that I've seen
many). For relatively-closeby IOs, the disk will always have a better
idea of how to optimise a number of IOs than the Linux elevator can
have, especially if we have multiple IOs spanning multiple heads
within a single cylinder.
--Stephen
next prev parent reply other threads:[~2002-03-04 19:56 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-02-22 15:57 [PATCH] 2.4.x write barriers (updated for ext3) James Bottomley
2002-02-22 16:10 ` Chris Mason
2002-02-22 16:13 ` Stephen C. Tweedie
2002-02-22 17:36 ` James Bottomley
2002-02-22 18:14 ` Chris Mason
2002-02-28 15:36 ` James Bottomley
2002-02-28 15:55 ` Chris Mason
2002-02-28 17:58 ` Mike Anderson
2002-02-28 18:12 ` Chris Mason
2002-03-01 2:08 ` James Bottomley
2002-03-03 22:11 ` Daniel Phillips
2002-03-04 3:34 ` Chris Mason
2002-03-04 5:05 ` Daniel Phillips
2002-03-04 15:03 ` James Bottomley
2002-03-04 17:04 ` Stephen C. Tweedie
2002-03-04 17:16 ` Chris Mason
2002-03-04 18:05 ` Stephen C. Tweedie
2002-03-04 18:28 ` James Bottomley
2002-03-04 19:55 ` Stephen C. Tweedie [this message]
2002-03-04 19:48 ` Daniel Phillips
2002-03-04 19:57 ` Stephen C. Tweedie
2002-03-04 21:06 ` Daniel Phillips
2002-03-05 14:58 ` Stephen C. Tweedie
2002-03-05 7:48 ` Jens Axboe
2002-03-04 19:51 ` Daniel Phillips
2002-03-05 7:42 ` Jens Axboe
2002-03-04 17:35 ` James Bottomley
2002-03-04 17:48 ` Chris Mason
2002-03-04 18:11 ` James Bottomley
2002-03-04 18:41 ` Chris Mason
2002-03-04 21:34 ` Stephen C. Tweedie
2002-03-04 18:09 ` Stephen C. Tweedie
2002-03-04 8:19 ` Helge Hafting
2002-03-04 14:57 ` James Bottomley
2002-03-04 17:24 ` Chris Mason
2002-03-04 19:02 ` Daniel Phillips
2002-03-05 7:22 ` Jeremy Higdon
2002-03-05 23:01 ` Daniel Phillips
2002-03-04 4:21 ` Jeremy Higdon
2002-03-04 5:31 ` Daniel Phillips
2002-03-04 6:09 ` Jeremy Higdon
2002-03-04 7:57 ` Daniel Phillips
2002-03-05 7:09 ` Jeremy Higdon
2002-03-05 22:56 ` Daniel Phillips
2002-03-04 16:52 ` Stephen C. Tweedie
2002-03-04 18:15 ` Daniel Phillips
2002-03-05 7:40 ` Jens Axboe
2002-03-05 22:29 ` Daniel Phillips
2002-03-12 7:01 ` Jens Axboe
2002-03-10 5:24 ` Douglas Gilbert
2002-03-11 11:13 ` Kurt Garloff
2002-03-12 1:17 ` GOTO Masanori
2002-03-12 6:58 ` Jens Axboe
2002-03-13 22:37 ` Peter Osterlund
2002-03-11 11:34 ` Stephen C. Tweedie
2002-03-11 17:15 ` James Bottomley
2002-03-04 14:48 ` James Bottomley
2002-03-06 13:59 ` Daniel Phillips
2002-03-06 14:34 ` James Bottomley
2002-02-25 10:57 ` Helge Hafting
2002-02-25 15:04 ` James Bottomley
-- strict thread matches above, loose matches on Subject: below --
2002-03-01 15:26 Dieter Nützel
2002-03-01 16:00 ` James Bottomley
2002-02-21 23:30 Chris Mason
2002-02-22 14:19 ` Stephen C. Tweedie
2002-02-22 15:26 ` Chris Mason
2002-01-10 9:55 [ANNOUNCE] FUSE: Filesystem in Userspace 0.95 Miklos Szeredi
2002-01-13 3:10 ` Pavel Machek
2002-01-21 10:18 ` Miklos Szeredi
2002-01-23 10:47 ` Pavel Machek
2002-01-22 19:07 ` Daniel Phillips
2002-01-23 2:33 ` [Avfs] " Justin Mason
2002-01-23 5:26 ` Daniel Phillips
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=20020304195537.I1444@redhat.com \
--to=sct@redhat.com \
--cc=James.Bottomley@steeleye.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=mason@suse.com \
--cc=phillips@bonn-fries.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 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.