On Fri, Aug 17, 2012 at 02:09:15PM +0800, Fengguang Wu wrote: > Ted, > > I find ext4 write performance dropped by 3.3% on average in the > 3.6-rc1 merge window. xfs and btrfs are fine. > > Two machines are tested. The performance regression happens in the > lkp-nex04 machine, which is equipped with 12 SSD drives. lkp-st02 does > not see regression, which is equipped with HDD drives. I'll continue > to repeat the tests and report variations. Hmm... I've checked out the commits in "git log v3.5..v3.6-rc1 -- fs/ext4 fs/jbd2" and I don't see anything that I would expect would cause that. The are the lock elimination changes for Direct I/O overwrites, but that shouldn't matter for your tests which are measuring buffered writes, correct? Is there any chance you could do me a favor and do a git bisect restricted to commits involving fs/ext4 and fs/jbd2? Many thanks, - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
