I have located 4.3.0-rc7 binaries which I will now try.
On Mon, Oct 26, 2015 at 3:38 PM, cheater00 . <cheate...@gmail.com> wrote: > Thanks for the reply. What version did this go into? I'll try getting > a prebuilt backport of the kernel, building source could slow things > down considerably, but debs will not be available for the latest few > minor versions I guess. So if you can tell me a min version, I'll try > to find the latest deb newer than that, or I'll build if that's not > available. > > On Mon, Oct 26, 2015 at 3:25 PM, Liu Bo <bo.li....@oracle.com> wrote: >> On 10/26/2015 08:16 PM, cheater00 . wrote: >>> >>> Hi guys, >>> I am running into really bad performance. Here's my setup: >>> >>> WD Red 6 TB connected over USB2 to my core i7 laptop, running Ubuntu >>> 32-bit with kernel 4.0.4-040004-generic #201505171336. >>> >>> Single btrfs partition covering whole disk. >>> >>> Autodefrag is on. >>> >>> fstab line: >>> UUID=... /media/X btrfs rw,nosuid,nodev,autodefrag 0 0 >>> >>> Sometimes when files are being modified or removed, I see >>> btrfs-transacti eat 100% cpu; during this time no io operations >>> succeed, that is, they're all stalled. You can't even ls on that fs. >>> This happens for several minutes then normal operation resumes. There >>> doesn't seem to be a rule to what will trigger this, other than >>> opening a single file and reading usually works quite well. (say, >>> watching a movie while all other programs are closed). But even moving >>> files off the disks triggers some sort of bug. Just now I am moving a >>> few files (just 30gb worth) onto another disk, and the bug triggers. >>> So btrfs-transacti was eating my cpu for over 5 minutes and according >>> to mv's output after this was done and cpu usage went back to normal >>> what I was waiting for was for a tiny png file to be removed. This is >>> pretty bad. >>> >>> I have tried defragmenting directories where files are being accessed >>> and moved. This hasn't helped. >>> >>> This happens whether the FS is near full or not. It currently is near >>> full but it wasn't before and it still did that. It still has about ~ >>> 100GB free space now. >>> >>> The more things are happening the more often this bug gets triggered. >>> So if I have utorrent running and its temporary downloads directory is >>> there, its download speed graph will be a few spikes of running at >>> several MB/sec separated by durations of 0 download speed. >>> >>> Nothing seems to show up in dmesg or syslog. >>> >>> I have asked in #btrfs but the suggestions ended up not fixing the >>> issue (autodefrag, defrag dirs). >>> >>> Please advise what I should do with this issue. >> >> >> It might be related to delayed ref rework, the last time I saw this kind of >> hanging problem about btrfs-transaction eating cpu is that because btrfs >> doesn't merge delayed refs, it'd be best to try the lastest kernel and if >> the issue is not resolved, then we can work out a reproducer and provide >> debugging. >> >> Thanks, >> >> Liubo -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
