All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dave Chinner <david@fromorbit.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: xfs@oss.sgi.com, Alex Elder <aelder@sgi.com>
Subject: Re: [PATCH 04/11] xfs: call xfs_buf_delwri_queue directly
Date: Fri, 2 Sep 2011 10:17:47 +1000	[thread overview]
Message-ID: <20110902001747.GR32358@dastard> (raw)
In-Reply-To: <20110901214640.GB4579@infradead.org>

On Thu, Sep 01, 2011 at 05:46:40PM -0400, Christoph Hellwig wrote:
> On Thu, Sep 01, 2011 at 02:22:15PM -0500, Alex Elder wrote:
> > that the buffer should be queued at unlock time, we now
> > just put it in the queue right away.  Seems reasonable.
> > Do you know why enqueueing it was delayed before?
> 
> I don't know why - it's a carryover from IRIX days,

Right. On Irix a buffer could simply have the BUF_DELWRI flag set on
it, and the buffer cache would take care of everything else. There
wasn't a specific delayed write list in Irix, instead there was a
fixed table of buffers (large!) that was scanned every 5 seconds
(20% scanned once per second) and the delwri buffers were gathered
by the scan.  Hence there were places in XFS where it simply set the
flag to mark a buffer delwri, and that's what this Linux code had to
catch.

> so long before my time.

The XFS code long predates me, too, but I spend a couple of years in
the trenches around the Irix buffer cache when I was at SGI so I at
least know why it was like that. ;)

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

  reply	other threads:[~2011-09-02  0:17 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-23  8:28 [PATCH 00/11] patch queue for Linux 3.2 Christoph Hellwig
2011-08-23  8:28 ` [PATCH 01/11] xfs: remove delwri buffer handling from xfs_buf_iorequest Christoph Hellwig
2011-09-01 19:21   ` Alex Elder
2011-08-23  8:28 ` [PATCH 02/11] xfs: remove the unlock argument to xfs_buf_delwri_queue Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-09-01 21:39     ` Christoph Hellwig
2011-08-23  8:28 ` [PATCH 03/11] xfs: move more delwri setup into xfs_buf_delwri_queue Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 04/11] xfs: call xfs_buf_delwri_queue directly Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-09-01 21:46     ` Christoph Hellwig
2011-09-02  0:17       ` Dave Chinner [this message]
2011-08-23  8:28 ` [PATCH 05/11] xfs: let xfs_bwrite callers handle the xfs_buf_relse Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 06/11] xfs: use the "delwri" terminology consistently Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 07/11] xfs: remove dead ENODEV handling in xfs_destroy_ioend Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 08/11] xfs: defer AIO/DIO completions Christoph Hellwig
2011-08-24  0:01   ` Dave Chinner
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 09/11] xfs: reduce ioend latency Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 10/11] xfs: wait for I/O completion when writing out pages in xfs_setattr_size Christoph Hellwig
2011-09-01 19:22   ` Alex Elder
2011-08-23  8:28 ` [PATCH 11/11] xfs: remove i_iocount Christoph Hellwig
2011-09-01 19:22   ` Alex Elder

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=20110902001747.GR32358@dastard \
    --to=david@fromorbit.com \
    --cc=aelder@sgi.com \
    --cc=hch@infradead.org \
    --cc=xfs@oss.sgi.com \
    /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.