Re: [linux-lvm] Pvmove can work on cluster with LVM 2.02.120(2) (2015-05-15), or not?

["Gang He" <ghe@suse.com>]

Hello Zdenek,

Do you remember LVM for this version supports PVmove, or not?
Since there is a user which is pinging this question.

Thanks
Gang


>>> 
> Hello List,
> 
> This is another pvmove problem, the LVM version is 2.02.120(2) (2015-05-15).
> This bug can be reproduced (not each time, but very easy),
> the problem is, online pvmove brings the upper file system hang.
> the environment is a three-node cluster (CLVM+OCFS2).
> 1) create two PV, create one VG, create one LV.
> sles12sp3r1-nd1:/ # pvs
>   PV         VG          Fmt  Attr PSize   PFree
>   /dev/sda1  cluster-vg2 lvm2 a--  120.00g 60.00g
>   /dev/sda2              lvm2 ---   30.00g 30.00g
>   /dev/sdb1  cluster-vg2 lvm2 a--  120.00g 60.00g
>   /dev/sdb2              lvm2 ---   30.00g 30.00g
> sles12sp3r1-nd1:/ # vgs
>   VG          #PV #LV #SN Attr   VSize   VFree
>   cluster-vg2   2   2   0 wz--nc 239.99g 119.99g
> sles12sp3r1-nd1:/ # lvs
>   LV       VG          Attr       LSize  Pool Origin Data%  Meta%  Move Log
> Cpy%Sync Convert
>   test-lv  cluster-vg2 -wI-ao---- 20.00g
> 
> 2) mkfs.ocfs2 test-lv LV, and mount this LV on each node.
> mkfs.ocfs2 -N 4 /dev/cluster-vg2/test-lv (on one node)
> mount /dev/cluster-vg2/test-lv  /mnt/shared (on each node)
> 
> 3) write/truncate some files in /mnt/shared from each node continually.
> 
> 4) run pvmove command on node1 while step 3) is in progress on each node.
> sles12sp3r1-nd1:/ # pvmove -i 5 /dev/sda1 /dev/sdb1
> Pvmove process will enter this stack,
> sles12sp3r1-nd1:/ # cat /proc/12748/stack
> [<ffffffff810f429f>] hrtimer_nanosleep+0xaf/0x170
> [<ffffffff810f43b6>] SyS_nanosleep+0x56/0x70
> [<ffffffff8160916e>] entry_SYSCALL_64_fastpath+0x12/0x6d
> [<ffffffffffffffff>] 0xffffffffffffffff
> 
> 5)Then, I can encounter ocfs2 file system write/truncate process hang
> problem on each node,
> The root cause is blocked at getting journal lock.
> but the journal lock is being used by ocfs2_commit thread, this thread is
> blocked at flushing journal to the disk (LVM disk).
> sles12sp3r1-nd3:/ # cat /proc/2310/stack
> [<ffffffffa021ab4a>] jbd2_log_wait_commit+0x8a/0xf0 [jbd2]
> [<ffffffffa021e5c7>] jbd2_journal_flush+0x47/0x180 [jbd2]
> [<ffffffffa04d2621>] ocfs2_commit_thread+0xa1/0x350 [ocfs2]
> [<ffffffff8109b627>] kthread+0xc7/0xe0
> [<ffffffff8160617f>] ret_from_fork+0x3f/0x70
> [<ffffffff8109b560>] kthread+0x0/0xe0
> [<ffffffffffffffff>] 0xffffffffffffffff
> 
> So, I want to confirm if online pvmove is supported by LVM 2.02.120(2)
> (2015-05-15)?
> If yes, how to debug this bug? it looks ocfs2 journal thread can not flush
> data to the underlying LVM disk.
> 
> Thanks
> Gang