linux-scsi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@suse.de>
To: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Jeremy Higdon <jeremy@sgi.com>,
	Andrew Vasquez <andrew.vasquez@qlogic.com>,
	SCSI Mailing List <linux-scsi@vger.kernel.org>
Subject: Re: [RFC PATCH 2.6.9-rc2] Add sysfs queue depth override to qla2xxx
Date: Tue, 28 Sep 2004 22:12:57 +0200	[thread overview]
Message-ID: <20040928201257.GA22509@suse.de> (raw)
In-Reply-To: <1096401196.2008.97.camel@mulgrave>

On Tue, Sep 28 2004, James Bottomley wrote:
> On Tue, 2004-09-28 at 15:36, Jeremy Higdon wrote:
> > I was trying to be conservative -- I didn't know the reason for
> > that limit.  By all means, let's remove it then.
> > 
> > Would you like me to regenerate the patch, or do you just want
> > to apply it to your internal source that will eventually be
> > fed back to us?
> 
> Well, don't go overboard on this ... there is a limit to the number of
> outstanding requests any queue can have at one time...there's not much
> point going over that since the block layer will throttle you when you
> reach it.  I think it's 128, but it might be 256 ... but anyway, not
> much larger.

That depends on both the io scheduler and the nr_requests setting, I
don't think you should rely on any imposed block layer limit.

-- 
Jens Axboe


  reply	other threads:[~2004-09-28 20:13 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-09-28 16:52 [RFC PATCH 2.6.9-rc2] Add sysfs queue depth override to qla2xxx Andrew Vasquez
2004-09-28 19:36 ` Jeremy Higdon
2004-09-28 19:53   ` James Bottomley
2004-09-28 20:12     ` Jens Axboe [this message]
2004-09-28 20:34       ` Andrew Vasquez
2004-09-29  6:21         ` Jens Axboe
2004-09-29  6:57           ` Jeremy Higdon
2004-09-29  6:56             ` Jens Axboe
2004-09-29  0:36     ` Jeremy Higdon
2004-09-29 16:41       ` Andrew Vasquez
2004-09-29 22:12         ` Jeremy Higdon
  -- strict thread matches above, loose matches on Subject: below --
2004-09-28 16:54 Andrew Vasquez
2004-09-27  6:10 Jeremy Higdon
2004-09-27  6:25 ` Jeremy Higdon
2004-09-28  7:54 ` Jeremy Higdon
2004-09-28 14:05   ` James Bottomley

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=20040928201257.GA22509@suse.de \
    --to=axboe@suse.de \
    --cc=James.Bottomley@SteelEye.com \
    --cc=andrew.vasquez@qlogic.com \
    --cc=jeremy@sgi.com \
    --cc=linux-scsi@vger.kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).