ocfs2: add a mount option journal_async_commit on ocfs2 filesystem
Add a mount option to support JBD2 feature:
JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT. When this feature is opened, journal
commit block can be written to disk without waiting for descriptor blocks,
which can improve journal commit performance. This option will enable
'journal_checksum' internally.
Using the fs_mark benchmark, using journal_async_commit shows a 50%
improvement, the files per second go up from 215.2 to 317.5.
test script:
fs_mark -d /mnt/ocfs2/ -s 10240 -n 1000
default:
FSUse% Count Size Files/sec App Overhead
0 1000 10240 215.2 17878
with journal_async_commit option:
FSUse% Count Size Files/sec App Overhead
0 1000 10240 317.5 17881
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Signed-off-by: Weiwei Wang <wangww631@huawei.comm>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt
index 7618a28..28f8c08 100644
--- a/Documentation/filesystems/ocfs2.txt
+++ b/Documentation/filesystems/ocfs2.txt
@@ -100,3 +100,7 @@
coherency=buffered Allow concurrent O_DIRECT writes without EX lock among
nodes, which gains high performance at risk of getting
stale data on other nodes.
+journal_async_commit Commit block can be written to disk without waiting
+ for descriptor blocks. If enabled older kernels cannot
+ mount the device. This will enable 'journal_checksum'
+ internally.