Locked up processes after upgrade to ZFS v15

[Jeremy Chadwick]

On Tue, Oct 12, 2010 at 05:40:21PM +0300, Andriy Gapon wrote:
> on 12/10/2010 17:35 Jeremy Chadwick said the following:
> > Nope, but since it's a single-CPU system I can probably enable it
> > safely (I thought I remember something about CTF not working right on
> > SMP systems...).  Give me a little while to figure out how to get it
> 
> Never heard about such issue and never hit them on my two-core systems.

What I'm remembering (two issues) are below, but apply to RELENG_7.
Sounds like issue may have gotten addressed in RELENG_8.

http://lists.freebsd.org/pipermail/freebsd-stable/2008-September/045093.html
http://lists.freebsd.org/pipermail/freebsd-stable/2008-September/045180.html

> > working, assuming you're willing to step me through what I need to do to
> > simulate the lock condition.  :-)
> 
> Enabling DTrace is really easy:
> http://wiki.freebsd.org/DTrace
> 
> I would appreciate if you could enable it on your test system.

Got it -- just finished and is currently running/working.  I also
installed ports/sysutils/DTraceToolkit and shells/ksh93 "just in case".

testbox# dtrace -l | head
   ID   PROVIDER            MODULE                          FUNCTION NAME
    1     dtrace                                                     BEGIN
    2     dtrace                                                     END
    3     dtrace                                                     ERROR
    4   dtmalloc                                                 fbt malloc
    5   dtmalloc                                                 fbt free
    6   dtmalloc                                              cyclic malloc
    7   dtmalloc                                              cyclic free
    8   dtmalloc                                          zones_data malloc
    9   dtmalloc                                          zones_data free

I can provide you root-level access to the box as well as serial console
if you'd prefer to do the debugging yourself, otherwise step me through
what's needed and I'll be happy to act as remote hands.

This should prove educational in another way, as I use Solaris regularly
at work but have never sat down to tinker with DTrace (just basic mdb
and adb).  Fun fun fun.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |