Resending as plain text. ---------- Forwarded message ---------- From: John <jello@xxxxxxxxx> Date: Mon, Oct 10, 2011 at 9:34 PM Subject: Re: fixing slow sync(2) To: Josef Bacik <josef@xxxxxxxxxx> Cc: Tomas Carnecky <tom@xxxxxxxxxxxxx>, linux-btrfs@xxxxxxxxxxxxxxx On Sat, Oct 8, 2011 at 10:35 AM, Josef Bacik <josef@xxxxxxxxxx> wrote: > > I think I fixed this, try my git tree > > git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work.git > > Let me know if it helps. And what are you doing when you call sync? I've not > been able to reproduce this problem so I'm having a hard time nailing down what > it is, so if I can get a reliable way to reproduce it I'll try and figure it > out. Thanks, I've been seeing very slow syncs (and unmounts) and this helps. Under 3.0.0 if I mounted the FS (which is 200G, about 97G used with ~720 snapshots) it took about 3 minutes 40 seconds. If I did another sync right away it took the same amount of time. With a kernel compiled from your repo the first time I sync it takes about 1 minute, as soon as I sync a btrfs-endio-met and btrfs-cache-0 process show up in top and a lot of IO happens. Once those go away (which takes a couple minutes) then it takes well under a second. If I unmount and remount it acts exactly the same. Will those changes be up in 3.1 or 3.2? If you want me to test anything else, I'm happy to do so. Thanks much. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
