From: Fengguang Wu <fengguang.wu@intel.com>
To: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>,
Andrew Morton <akpm@linux-foundation.org>,
Jeff Moyer <jmoyer@redhat.com>, Jens Axboe <axboe@kernel.dk>,
linux-fsdevel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
Dave Chinner <david@fromorbit.com>,
Christoph Hellwig <hch@infradead.org>,
Shaohua Li <shli@fusionio.com>
Subject: [PATCH] btrfs: lower metadata writeback threshold on low dirty threshold
Date: Thu, 3 May 2012 11:43:11 +0800 [thread overview]
Message-ID: <20120503034311.GA14081@localhost> (raw)
In-Reply-To: <20120413014026.GA9027@localhost>
This helps write performance when setting the dirty threshold to tiny numbers.
3.4.0-rc2 3.4.0-rc2-btrfs4+
------------ ------------------------
96.92 -0.4% 96.54 bay/thresh=1000M/btrfs-100dd-1-3.4.0-rc2
98.47 +0.0% 98.50 bay/thresh=1000M/btrfs-10dd-1-3.4.0-rc2
99.38 -0.3% 99.06 bay/thresh=1000M/btrfs-1dd-1-3.4.0-rc2
98.04 -0.0% 98.02 bay/thresh=100M/btrfs-100dd-1-3.4.0-rc2
98.68 +0.3% 98.98 bay/thresh=100M/btrfs-10dd-1-3.4.0-rc2
99.34 -0.0% 99.31 bay/thresh=100M/btrfs-1dd-1-3.4.0-rc2
==> 88.98 +9.6% 97.53 bay/thresh=10M/btrfs-10dd-1-3.4.0-rc2
==> 86.99 +13.1% 98.39 bay/thresh=10M/btrfs-1dd-1-3.4.0-rc2
==> 2.75 +2442.4% 69.88 bay/thresh=1M/btrfs-10dd-1-3.4.0-rc2
==> 3.31 +2634.1% 90.54 bay/thresh=1M/btrfs-1dd-1-3.4.0-rc2
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
---
fs/btrfs/disk-io.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- linux-next.orig/fs/btrfs/disk-io.c 2012-05-02 14:04:00.989262395 +0800
+++ linux-next/fs/btrfs/disk-io.c 2012-05-02 14:04:01.773262414 +0800
@@ -930,7 +930,8 @@ static int btree_writepages(struct addre
/* this is a bit racy, but that's ok */
num_dirty = root->fs_info->dirty_metadata_bytes;
- if (num_dirty < thresh)
+ if (num_dirty < min(thresh,
+ global_dirty_limit << (PAGE_CACHE_SHIFT-2)))
return 0;
}
return btree_write_cache_pages(mapping, wbc);
next prev parent reply other threads:[~2012-05-03 3:43 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-08 1:06 [RESEND][PATCH v2] block: remove plugging at buffered write time Wu Fengguang
2012-04-09 14:34 ` Jeff Moyer
2012-04-11 23:13 ` Andrew Morton
2012-04-12 1:32 ` Fengguang Wu
2012-04-12 2:20 ` Fengguang Wu
2012-04-12 14:26 ` Jan Kara
2012-04-13 1:40 ` Fengguang Wu
2012-05-03 3:43 ` Fengguang Wu [this message]
2012-05-03 3:53 ` [PATCH] writeback: initialize global_dirty_limit Fengguang Wu
2012-05-03 9:25 ` [PATCH] btrfs: lower metadata writeback threshold on low dirty threshold Jan Kara
2012-05-03 10:02 ` Fengguang Wu
2012-05-03 12:31 ` Chris Mason
2012-05-03 13:30 ` Josef Bacik
2012-05-03 14:08 ` Fengguang Wu
2012-05-06 6:01 ` [RESEND][PATCH v2] block: remove plugging at buffered write time Fengguang Wu
2012-05-06 9:58 ` Fengguang Wu
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=20120503034311.GA14081@localhost \
--to=fengguang.wu@intel.com \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=chris.mason@oracle.com \
--cc=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=jack@suse.cz \
--cc=jmoyer@redhat.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=shli@fusionio.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 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).