On Tue, Feb 23, 2016 at 05:56:58PM -0800, Marc MERLIN wrote: > On Tue, Feb 23, 2016 at 08:40:46PM -0400, Kenny MacDermid wrote: > > I'm running btrfs on DM-Crypt Luks running on LVM. > > > > Occasionally I get files that are unreadable for some period of time. > > Attempting to read from them results in an > > > > Input/output error > > > > Sometimes they'll come back on their own, and sometimes a scrub seems to > > help, but sometimes I just have to delete them. > > > > Nothing shows up in dmesg when these occur, and I can't predict which > > files it will be, or what causes it. > > > > It's currently happening running 4.4.1-2-ARCH, but I've seen the same > > thing for many previous kernel versions. > > > > Does anyone have any suggestions? > > That's weird to say the least, you should at least get *something* in > dmesg. > And you are getting other error messages and btrfs kernel messages in > your logs? > > When whatever app you have that's trying to read them fails, I assume > they also fail with cat or less? I am getting other, normal btrfs messages. I'll include them at the end. When it happens I get nothing at all in dmesg/logs. And yes, cat will fail. I can move the file to another name though, which I often do to get it out of the way. They're mounted with: rw,noatime,compress=lzo,ssd,discard,space_cache,autodefrag,inode_cache issue_discards=1 is in lvm.conf, and discard in /etc/crypttab. (I'm now reading that I probably shouldn't have it in fstab though and just run fstrim.) I don't know if this is related yet at all, but it /seems/ more likely to happen after I delete a bunch of data. That could be a red herring though. When the file becomes readable again it's perfectly fine. Scrub never finds any errors. $ dmesg | grep -i btrfs [ 11.837137] Btrfs loaded [ 11.837403] BTRFS: device label root devid 1 transid 508963 /dev/dm-3 [ 11.856203] BTRFS info (device dm-3): disk space caching is enabled [ 11.879366] BTRFS: detected SSD devices, enabling SSD mode [ 12.160267] BTRFS info (device dm-3): turning on discard [ 12.160272] BTRFS info (device dm-3): enabling auto defrag [ 12.160275] BTRFS info (device dm-3): enabling inode map caching [ 12.160277] BTRFS info (device dm-3): disk space caching is enabled [ 14.979093] BTRFS: device label home devid 1 transid 705779 /dev/dm-5 [ 15.013978] BTRFS info (device dm-5): use ssd allocation scheme [ 15.013983] BTRFS info (device dm-5): turning on discard [ 15.013987] BTRFS info (device dm-5): enabling auto defrag [ 15.013989] BTRFS info (device dm-5): enabling inode map caching [ 15.013991] BTRFS info (device dm-5): disk space caching is enabled [ 15.100779] BTRFS error (device dm-5): could not find root 8 [ 15.102889] BTRFS error (device dm-5): could not find root 8 [ 15.105833] BTRFS error (device dm-3): could not find root 8 [ 15.105838] BTRFS error (device dm-3): could not find root 8 -- 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
