8.1R possible zfs snapshot livelock?

[Andriy Gapon]

on 18/05/2011 04:49 Charles Sprickman said the following:
> On Tue, 17 May 2011, Andriy Gapon wrote:
>> Less drastic approach to hanged I/O debugging is to find out where
>> processes/threads are actually stuck.  E.g. using procstat -kk.
> 
> Odd you say that because we've got an old 32-bit 8.1 box that's running
> spamassassin and some devel stuff that looks like it's getting a little wedged:
> 
>   PID USERNAME  THR PRI NICE   SIZE    RES STATE    TIME   WCPU COMMAND
>     6 root        4  -8    -     0K    36K tx->tx 126.0H 76.37% zfskern
> 
> And I'm not sure "procstat" is meant for this, but the output is interesting:

It is.

> [root at h22 /home/spork]# procstat -k 6
>   PID    TID COMM             TDNAME           KSTACK
>     6 100053 zfskern          arc_reclaim_thre mi_switch sleepq_switch
> sleepq_timedwait _cv_timedwait arc_reclaim_thread fork_exit fork_trampoline
>     6 100054 zfskern          l2arc_feed_threa mi_switch sleepq_switch
> sleepq_timedwait _cv_timedwait l2arc_feed_thread fork_exit fork_trampoline
>     6 100093 zfskern          txg_thread_enter mi_switch sleepq_switch
> sleepq_wait _cv_wait txg_thread_wait txg_quiesce_thread fork_exit fork_trampoline
>     6 100094 zfskern          txg_thread_enter mi_switch sleepq_switch
> sleepq_timedwait _cv_timedwait txg_thread_wait txg_sync_thread fork_exit
> fork_trampoline

This looks completely normal.

-- 
Andriy Gapon