From 0390131ba84fd3f726f9e24fc4553828125700bb Mon Sep 17 00:00:00 2001 From: Frank Mayhar Date: Wed, 7 Jan 2009 00:06:22 -0500 Subject: ext4: Allow ext4 to run without a journal A few weeks ago I posted a patch for discussion that allowed ext4 to run without a journal. Since that time I've integrated the excellent comments from Andreas and fixed several serious bugs. We're currently running with this patch and generating some performance numbers against both ext2 (with backported reservations code) and ext4 with and without a journal. It just so happens that running without a journal is slightly faster for most everything. We did iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2 which creates 4 threads, each of which create and do reads and writes on a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens to bypass the page cache. Results: ext2 ext4, default ext4, no journal initial writes 13.0 MB/s 15.4 MB/s 15.7 MB/s rewrites 13.1 MB/s 15.6 MB/s 15.9 MB/s reads 15.2 MB/s 16.9 MB/s 17.2 MB/s re-reads 15.3 MB/s 16.9 MB/s 17.2 MB/s random readers 5.6 MB/s 5.6 MB/s 5.7 MB/s random writers 5.1 MB/s 5.3 MB/s 5.4 MB/s So it seems that, so far, this was a useful exercise. Signed-off-by: Frank Mayhar Signed-off-by: "Theodore Ts'o" --- fs/ext4/balloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/ext4/balloc.c') diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 35f5f9a27722..31ebeb5e7b07 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -531,11 +531,11 @@ do_more: /* We dirtied the bitmap block */ BUFFER_TRACE(bitmap_bh, "dirtied bitmap block"); - err = ext4_journal_dirty_metadata(handle, bitmap_bh); + err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh); /* And the group descriptor block */ BUFFER_TRACE(gd_bh, "dirtied group descriptor block"); - ret = ext4_journal_dirty_metadata(handle, gd_bh); + ret = ext4_handle_dirty_metadata(handle, NULL, gd_bh); if (!err) err = ret; *pdquot_freed_blocks += group_freed; -- cgit v1.2.3