Date: Fri, 9 Jun 2017 12:15:32 +0200 From: =?UTF-8?Q?=c5=81ukasz_W=c4=85sikowski?= <lukasz@wasikowski.net> To: Stephen McKay <mckay@FreeBSD.org> Cc: freebsd-fs@freebsd.org Subject: Re: Problem with zpool remove of log device Message-ID: <cd18dc67-cbaf-1178-1515-abcaa7fb4ccc@wasikowski.net> In-Reply-To: <0fc687$sij78n@ipmail05.adl6.internode.on.net> References: <9188a169-cd81-f64d-6b9e-0e3c6b4af1bb@wasikowski.net> <0410af$1dldvp4@ipmail04.adl6.internode.on.net> <4df1ea6d-148e-f3ab-d204-9277c513a468@wasikowski.net> <0fc687$sij78n@ipmail05.adl6.internode.on.net>
next in thread | previous in thread | raw e-mail | index | archive | help
W dniu 2017-06-09 o 05:18, Stephen McKay pisze: > On Wednesday, 7th June 2017, =?UTF-8?Q?=c5=81ukasz_W=c4=85sikowski?= wrote: > >> W dniu 2017-06-07 o 10:21, Stephen McKay pisze: >> >>> On Friday, 26th May 2017, lukasz@wasikowski.net wrote: >>> >>>> I cant remove log device from pool - operation ends ok, but log device >>>> is still in the pool (bug?). > >>> Does your system still write to the log? Use "zfs iostat -v 1" to >>> check. I think it is probably no longer be in use and only the final >>> disconnection failed. >> >> zpool iostat -v 1 shows no activity on the log drive. I tried to remove >> it after booting to livecd - no luck. > > I hope I haven't mislead you there (more than misspelling zpool, that is). > > In normal operation the log is idle unless there are synchronous writes > to log. So, to be sure your log is active, use something like this (within > the target pool) to generate sync writes: > > while : > do > date > foo > fsync foo > done > > With this running, my system does 600 writes per second to the log > according to zpool iostat. That drops to zero once I kill the script. Zero, so no writes to log are performed during execution of this script. >>> I had this problem when I tried to remove a log mirror from a pool >>> I have been using for years. I solved it by tweaking the zfsonlinux >>> hack a bit and slotting it into 9.3. >> >> Thank you for this info. It seems that it's no longer an issue for me - >> this box will be soon retired. I'll move some data from it and wipe it down. > > If you are feeling public spirited this is an ideal opportunity to check > the theory against reality. I'm curious about how widespread this accounting > bug is, so if you can keep the machine intact for a while after it has > been decommissioned, you could build a patched kernel and try to remove the > log again. All it would cost in this case is a little time. I applied this patch to 11.1-PRERELASE, nothing changed. Still zpool remove exits with errcode 0, but log device is still attached to pool. -- Z poważaniem, Łukasz Wąsikowski
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?cd18dc67-cbaf-1178-1515-abcaa7fb4ccc>