From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Johannes Weiner <jweiner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>,
Christoph Hellwig <hch@infradead.org>,
Dave Chinner <david@fromorbit.com>,
Wu Fengguang <fengguang.wu@intel.com>, Jan Kara <jack@suse.cz>,
Rik van Riel <riel@redhat.com>,
Minchan Kim <minchan.kim@gmail.com>,
Chris Mason <chris.mason@oracle.com>,
"Theodore Ts'o" <tytso@mit.edu>,
Andreas Dilger <adilger.kernel@dilger.ca>,
Shaohua Li <shaohua.li@intel.com>,
xfs@oss.sgi.com, linux-btrfs@vger.kernel.org,
linux-ext4@vger.kernel.org, linux-mm@kvack.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [patch 3/5] mm: try to distribute dirty pages fairly across zones
Date: Fri, 30 Sep 2011 10:35:25 +0300 [thread overview]
Message-ID: <CAOJsxLFWfH5zDG8ui=yQyOcZY_nXhK6r+ziapLg9Zhmb3ibuWQ@mail.gmail.com> (raw)
In-Reply-To: <1317367044-475-4-git-send-email-jweiner@redhat.com>
Hi Johannes!
On Fri, Sep 30, 2011 at 10:17 AM, Johannes Weiner <jweiner@redhat.com> wrot=
e:
> But there is a flaw in that we have a zoned page allocator which does
> not care about the global state but rather the state of individual
> memory zones. =A0And right now there is nothing that prevents one zone
> from filling up with dirty pages while other zones are spared, which
> frequently leads to situations where kswapd, in order to restore the
> watermark of free pages, does indeed have to write pages from that
> zone's LRU list. =A0This can interfere so badly with IO from the flusher
> threads that major filesystems (btrfs, xfs, ext4) mostly ignore write
> requests from reclaim already, taking away the VM's only possibility
> to keep such a zone balanced, aside from hoping the flushers will soon
> clean pages from that zone.
The obvious question is: how did you test this? Can you share the results?
Pekka
--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Johannes Weiner <jweiner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>,
Christoph Hellwig <hch@infradead.org>,
Dave Chinner <david@fromorbit.com>,
Wu Fengguang <fengguang.wu@intel.com>, Jan Kara <jack@suse.cz>,
Rik van Riel <riel@redhat.com>,
Minchan Kim <minchan.kim@gmail.com>,
Chris Mason <chris.mason@oracle.com>,
"Theodore Ts'o" <tytso@mit.edu>,
Andreas Dilger <adilger.kernel@dilger.ca>,
Shaohua Li <shaohua.li@intel.com>,
xfs@oss.sgi.com, linux-btrfs@vger.kernel.org,
linux-ext4@vger.kernel.org, linux-mm@kvack.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [patch 3/5] mm: try to distribute dirty pages fairly across zones
Date: Fri, 30 Sep 2011 10:35:25 +0300 [thread overview]
Message-ID: <CAOJsxLFWfH5zDG8ui=yQyOcZY_nXhK6r+ziapLg9Zhmb3ibuWQ@mail.gmail.com> (raw)
In-Reply-To: <1317367044-475-4-git-send-email-jweiner@redhat.com>
Hi Johannes!
On Fri, Sep 30, 2011 at 10:17 AM, Johannes Weiner <jweiner@redhat.com> wrote:
> But there is a flaw in that we have a zoned page allocator which does
> not care about the global state but rather the state of individual
> memory zones. And right now there is nothing that prevents one zone
> from filling up with dirty pages while other zones are spared, which
> frequently leads to situations where kswapd, in order to restore the
> watermark of free pages, does indeed have to write pages from that
> zone's LRU list. This can interfere so badly with IO from the flusher
> threads that major filesystems (btrfs, xfs, ext4) mostly ignore write
> requests from reclaim already, taking away the VM's only possibility
> to keep such a zone balanced, aside from hoping the flushers will soon
> clean pages from that zone.
The obvious question is: how did you test this? Can you share the results?
Pekka
WARNING: multiple messages have this Message-ID (diff)
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Johannes Weiner <jweiner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>,
Christoph Hellwig <hch@infradead.org>,
Dave Chinner <david@fromorbit.com>,
Wu Fengguang <fengguang.wu@intel.com>, Jan Kara <jack@suse.cz>,
Rik van Riel <riel@redhat.com>,
Minchan Kim <minchan.kim@gmail.com>,
Chris Mason <chris.mason@oracle.com>,
"Theodore Ts'o" <tytso@mit.edu>,
Andreas Dilger <adilger.kernel@dilger.ca>,
Shaohua Li <shaohua.li@intel.com>,
xfs@oss.sgi.com, linux-btrfs@vger.kernel.org,
linux-ext4@vger.kernel.org, linux-mm@kvack.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [patch 3/5] mm: try to distribute dirty pages fairly across zones
Date: Fri, 30 Sep 2011 10:35:25 +0300 [thread overview]
Message-ID: <CAOJsxLFWfH5zDG8ui=yQyOcZY_nXhK6r+ziapLg9Zhmb3ibuWQ@mail.gmail.com> (raw)
In-Reply-To: <1317367044-475-4-git-send-email-jweiner@redhat.com>
Hi Johannes!
On Fri, Sep 30, 2011 at 10:17 AM, Johannes Weiner <jweiner@redhat.com> wrote:
> But there is a flaw in that we have a zoned page allocator which does
> not care about the global state but rather the state of individual
> memory zones. And right now there is nothing that prevents one zone
> from filling up with dirty pages while other zones are spared, which
> frequently leads to situations where kswapd, in order to restore the
> watermark of free pages, does indeed have to write pages from that
> zone's LRU list. This can interfere so badly with IO from the flusher
> threads that major filesystems (btrfs, xfs, ext4) mostly ignore write
> requests from reclaim already, taking away the VM's only possibility
> to keep such a zone balanced, aside from hoping the flushers will soon
> clean pages from that zone.
The obvious question is: how did you test this? Can you share the results?
Pekka
--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>,
linux-ext4@vger.kernel.org, Jan Kara <jack@suse.cz>,
linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org,
xfs@oss.sgi.com, Christoph Hellwig <hch@infradead.org>,
linux-mm@kvack.org, Andreas Dilger <adilger.kernel@dilger.ca>,
Mel Gorman <mgorman@suse.de>, Shaohua Li <shaohua.li@intel.com>,
linux-fsdevel@vger.kernel.org, Theodore Ts'o <tytso@mit.edu>,
Andrew Morton <akpm@linux-foundation.org>,
Wu Fengguang <fengguang.wu@intel.com>,
Chris Mason <chris.mason@oracle.com>,
Minchan Kim <minchan.kim@gmail.com>
Subject: Re: [patch 3/5] mm: try to distribute dirty pages fairly across zones
Date: Fri, 30 Sep 2011 10:35:25 +0300 [thread overview]
Message-ID: <CAOJsxLFWfH5zDG8ui=yQyOcZY_nXhK6r+ziapLg9Zhmb3ibuWQ@mail.gmail.com> (raw)
In-Reply-To: <1317367044-475-4-git-send-email-jweiner@redhat.com>
Hi Johannes!
On Fri, Sep 30, 2011 at 10:17 AM, Johannes Weiner <jweiner@redhat.com> wrote:
> But there is a flaw in that we have a zoned page allocator which does
> not care about the global state but rather the state of individual
> memory zones. And right now there is nothing that prevents one zone
> from filling up with dirty pages while other zones are spared, which
> frequently leads to situations where kswapd, in order to restore the
> watermark of free pages, does indeed have to write pages from that
> zone's LRU list. This can interfere so badly with IO from the flusher
> threads that major filesystems (btrfs, xfs, ext4) mostly ignore write
> requests from reclaim already, taking away the VM's only possibility
> to keep such a zone balanced, aside from hoping the flushers will soon
> clean pages from that zone.
The obvious question is: how did you test this? Can you share the results?
Pekka
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next prev parent reply other threads:[~2011-09-30 7:35 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-30 7:17 [patch 0/5] per-zone dirty limits v3 Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` [patch 1/5] mm: exclude reserved pages from dirtyable memory Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 13:53 ` Michal Hocko
2011-09-30 13:53 ` Michal Hocko
2011-09-30 13:53 ` Michal Hocko
2011-10-01 7:10 ` Minchan Kim
2011-10-01 7:10 ` Minchan Kim
2011-10-01 7:10 ` Minchan Kim
2011-10-03 11:22 ` Mel Gorman
2011-10-03 11:22 ` Mel Gorman
2011-10-03 11:22 ` Mel Gorman
2011-09-30 7:17 ` [patch 2/5] mm: writeback: cleanups in preparation for per-zone dirty limits Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 13:56 ` Michal Hocko
2011-09-30 13:56 ` Michal Hocko
2011-09-30 13:56 ` Michal Hocko
2011-09-30 7:17 ` [patch 3/5] mm: try to distribute dirty pages fairly across zones Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:35 ` Pekka Enberg [this message]
2011-09-30 7:35 ` Pekka Enberg
2011-09-30 7:35 ` Pekka Enberg
2011-09-30 7:35 ` Pekka Enberg
2011-09-30 8:55 ` Johannes Weiner
2011-09-30 8:55 ` Johannes Weiner
2011-09-30 8:55 ` Johannes Weiner
2011-09-30 8:55 ` Johannes Weiner
2011-09-30 8:55 ` Johannes Weiner
2011-09-30 14:28 ` Michal Hocko
2011-09-30 14:28 ` Michal Hocko
2011-09-30 14:28 ` Michal Hocko
2011-10-28 20:18 ` Wu Fengguang
2011-10-28 20:18 ` Wu Fengguang
2011-10-28 20:18 ` Wu Fengguang
2011-10-31 11:33 ` Wu Fengguang
2011-10-31 11:33 ` Wu Fengguang
2011-10-31 11:33 ` Wu Fengguang
2011-11-01 10:55 ` Johannes Weiner
2011-11-01 10:55 ` Johannes Weiner
2011-11-01 10:55 ` Johannes Weiner
[not found] ` <20111027155618.GA25524@localhost>
[not found] ` <20111027161359.GA1319@redhat.com>
[not found] ` <20111027204743.GA19343@localhost>
[not found] ` <20111027221258.GA22869@localhost>
[not found] ` <20111027231933.GB1319@redhat.com>
2011-10-28 20:39 ` Wu Fengguang
2011-10-28 20:39 ` Wu Fengguang
2011-11-01 10:52 ` Johannes Weiner
2011-11-01 10:52 ` Johannes Weiner
2011-11-01 10:52 ` Johannes Weiner
2011-09-30 7:17 ` [patch 4/5] mm: filemap: pass __GFP_WRITE from grab_cache_page_write_begin() Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 14:41 ` Michal Hocko
2011-09-30 14:41 ` Michal Hocko
2011-09-30 14:41 ` Michal Hocko
2011-09-30 7:17 ` [patch 5/5] Btrfs: pass __GFP_WRITE for buffered write page allocations Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-09-30 7:17 ` Johannes Weiner
2011-10-03 11:25 ` Mel Gorman
2011-10-03 11:25 ` Mel Gorman
2011-10-03 11:25 ` Mel Gorman
2011-11-23 13:34 [patch 0/5] mm: per-zone dirty limits v3-resend Johannes Weiner
2011-11-23 13:34 ` [patch 3/5] mm: try to distribute dirty pages fairly across zones Johannes Weiner
2011-11-23 13:34 ` Johannes Weiner
2011-11-24 1:07 ` KAMEZAWA Hiroyuki
2011-11-24 1:07 ` KAMEZAWA Hiroyuki
2011-11-24 13:11 ` Johannes Weiner
2011-11-24 13:11 ` Johannes Weiner
2011-11-25 1:00 ` KAMEZAWA Hiroyuki
2011-11-25 1:00 ` KAMEZAWA Hiroyuki
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='CAOJsxLFWfH5zDG8ui=yQyOcZY_nXhK6r+ziapLg9Zhmb3ibuWQ@mail.gmail.com' \
--to=penberg@cs.helsinki.fi \
--cc=adilger.kernel@dilger.ca \
--cc=akpm@linux-foundation.org \
--cc=chris.mason@oracle.com \
--cc=david@fromorbit.com \
--cc=fengguang.wu@intel.com \
--cc=hch@infradead.org \
--cc=jack@suse.cz \
--cc=jweiner@redhat.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=minchan.kim@gmail.com \
--cc=riel@redhat.com \
--cc=shaohua.li@intel.com \
--cc=tytso@mit.edu \
--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.