linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Wu Fengguang <fengguang.wu@intel.com>
To: Dave Chinner <david@fromorbit.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Jan Kara <jack@suse.cz>, Mel Gorman <mel@csn.ul.ie>,
	Christoph Hellwig <hch@infradead.org>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 03/17] writeback: introduce writeback_control.inodes_cleaned
Date: Fri, 13 May 2011 11:36:05 +0800	[thread overview]
Message-ID: <20110513033605.GC8016@localhost> (raw)
In-Reply-To: <20110512224420.GJ19446@dastard>

On Fri, May 13, 2011 at 06:44:20AM +0800, Dave Chinner wrote:
> On Thu, May 12, 2011 at 09:57:09PM +0800, Wu Fengguang wrote:
> > The flusher works on dirty inodes in batches, and may quit prematurely
> > if the batch of inodes happen to be metadata-only dirtied: in this case
> > wbc->nr_to_write won't be decreased at all, which stands for "no pages
> > written" but also mis-interpreted as "no progress".
> > 
> > So introduce writeback_control.inodes_cleaned to count the inodes get
> > cleaned.  A non-zero value means there are some progress on writeback,
> > in which case more writeback can be tried.
> 
> Why introduce a new field for this?

Yeah sorry, but this is an intermediate field that will be removed in
patch 14.

> Just decrement nr_to_write for every write_inode() call made in
> writeback_single_inode()....

There are two problems

- nr_to_write has always been "# of pages written" and writeback_sb_inodes()
  is actually making use of it to do page accounting in work->nr_pages.

- write_inode() does not always succeed, and its return value is not
  reliable on every filesystem.. (I actually tried this approach in v1
  and found sync(1) hang on NFS)

Thanks,
Fengguang

  reply	other threads:[~2011-05-13  3:36 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-12 13:57 [PATCH 00/17] writeback fixes and cleanups for 2.6.40 (v2) Wu Fengguang
2011-05-12 13:57 ` [PATCH 01/17] writeback: introduce .tagged_sync for the WB_SYNC_NONE sync stage Wu Fengguang
2011-05-12 22:40   ` Dave Chinner
2011-05-13  2:56     ` Wu Fengguang
2011-05-13 10:17       ` Christoph Hellwig
2011-05-15 23:43       ` Dave Chinner
2011-05-16  5:39         ` Wu Fengguang
2011-05-19 21:17           ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 02/17] writeback: update dirtied_when for synced inode to prevent livelock Wu Fengguang
2011-05-12 22:42   ` Dave Chinner
2011-05-13  3:08     ` Wu Fengguang
2011-05-19 21:31       ` Wu Fengguang
2011-05-23 13:14         ` Jan Kara
2011-05-24  3:03           ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 03/17] writeback: introduce writeback_control.inodes_cleaned Wu Fengguang
2011-05-12 22:44   ` Dave Chinner
2011-05-13  3:36     ` Wu Fengguang [this message]
2011-05-15 23:50       ` Dave Chinner
2011-05-16 10:40         ` Christoph Hellwig
2011-05-16 11:14           ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 04/17] writeback: try more writeback as long as something was written Wu Fengguang
2011-05-12 13:57 ` [PATCH 05/17] writeback: the kupdate expire timestamp should be a moving target Wu Fengguang
2011-05-12 13:57 ` [PATCH 06/17] writeback: sync expired inodes first in background writeback Wu Fengguang
2011-05-12 22:55   ` Dave Chinner
2011-05-16 13:00     ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 07/17] writeback: refill b_io iff empty Wu Fengguang
2011-05-12 13:57 ` [PATCH 08/17] writeback: split inode_wb_list_lock into bdi_writeback.list_lock Wu Fengguang
2011-05-12 13:57 ` [PATCH 09/17] writeback: elevate queue_io() into wb_writeback() Wu Fengguang
2011-05-12 13:57 ` [PATCH 10/17] writeback: avoid extra sync work at enqueue time Wu Fengguang
2011-05-12 13:57 ` [PATCH 11/17] writeback: add bdi_dirty_limit() kernel-doc Wu Fengguang
2011-05-12 13:57 ` [PATCH 12/17] writeback: skip balance_dirty_pages() for in-memory fs Wu Fengguang
2011-05-16 10:43   ` Christoph Hellwig
2011-05-16 10:49     ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 13/17] writeback: remove writeback_control.more_io Wu Fengguang
2011-05-12 14:25   ` Minchan Kim
2011-05-12 23:04   ` Dave Chinner
2011-05-13  5:03     ` Wu Fengguang
2011-05-15 23:54       ` Dave Chinner
2011-05-12 13:57 ` [PATCH 14/17] writeback: make writeback_control.nr_to_write straight Wu Fengguang
2011-05-12 14:56   ` Jan Kara
2011-05-12 23:18   ` Dave Chinner
2011-05-13  5:28     ` Wu Fengguang
2011-05-16  0:12       ` Dave Chinner
2011-05-16 12:05         ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 15/17] writeback: remove .nonblocking and .encountered_congestion Wu Fengguang
2011-05-12 13:57 ` [PATCH 16/17] writeback: trace event writeback_single_inode Wu Fengguang
2011-05-12 23:20   ` Dave Chinner
2011-05-13  5:37     ` Wu Fengguang
2011-05-16  0:14       ` Dave Chinner
2011-05-16 12:21         ` Wu Fengguang
2011-05-12 13:57 ` [PATCH 17/17] writeback: trace event writeback_queue_io Wu Fengguang
  -- strict thread matches above, loose matches on Subject: below --
2011-05-06  3:08 [PATCH 00/17] writeback fixes and cleanups for 2.6.40 Wu Fengguang
2011-05-06  3:08 ` [PATCH 03/17] writeback: introduce writeback_control.inodes_cleaned Wu Fengguang
2011-05-06 14:36   ` Jan Kara
2011-05-10  2:23     ` Wu Fengguang
2011-05-10 13:52       ` Jan Kara
2011-05-10 15:00         ` Wu Fengguang

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=20110513033605.GC8016@localhost \
    --to=fengguang.wu@intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=david@fromorbit.com \
    --cc=hch@infradead.org \
    --cc=jack@suse.cz \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mel@csn.ul.ie \
    /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).