Chris Mason posted on Sun, 20 Jul 2014 10:33:24 -0400 as excerpted: > I was hoping to also include a fix for a btrfs deadlock with compression > enabled, but we're still nailing that one down.
FWIW, I might be (rarely but twice, now) hitting that one myself, compress=lzo, but /not/ with the rsync that has been your current primary trigger. The last time I hit it, it was trying to start firefox shortly after a fresh boot. Firefox didn't come up, and when I tried starting it again, I got the dialog saying it was already running, quit the running instance and try again, or reboot. But the running firefox instance was stuck unkillable in D state, with a zombie child. Three of my six cores were stuck in 100% IO-wait. I finished what I was doing and shut down X, but of course the D-state and zombie firefox reparented to systemd. The time before when that happened with firefox, I ended up losing several of the firefox state files and it forgot my extensions, which I had to restore from backup. So this time I mounted a reiserfs I use for other things and did a backup of the entire ~/.mozilla/ subdir before finishing the shutdown and reboot. That backup went fine (surprised me, I thought it might hang too), and I umounted the reiserfs. But when I went to finish the shutdown of course the affected btrfs wouldn't umount due to the stuck firefox. So I did the magic-SRQ REISUB thing, and saw the emergency sync and the remount-read-only complete. After that I force-rebooted. Luckily, this time I didn't need that backup of the ~/.mozilla subfolder I had made -- firefox came up fine after the reboot. But I did lose the read state on a few messages in my feed (rss/atom) and news (nntp) readers, so I think btrfs did lose the log from after the last root-tree commit point. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
