So far I cannot reproduce. If I don't post again this means the issue has been fixed by updating the kernel.
On Mon, Oct 26, 2015 at 4:40 PM, cheater00 . <cheate...@gmail.com> wrote: > 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
