[OpenIndiana-discuss] ZFS stalls with oi_151?

[Bryan S. Leaman]

On 10/21/2011 4:16 AM, Tommy Eriksen wrote:
> Hi guys,
>
> I've got a bit of a ZFS problem:
> All of a sudden, and it doesn't seem related to load or anything, the system will stop writing to the disks in my storage pool. No error messages are logged (that I can find anyway), nothing in dmesg, messages or the likes.
>
> ZFS stalls, a simple snapshot command (or the likes) just hangs indefinitely and can't be stopped with ctrl+c or kill -9.
>
> Today, the stall happened after I had been running 2 VMs on each (running on vsphere5 connecting via iscsi) running iozone -s 200G (just to generate a bunch of load). Happily, this morning, I saw that they were still running without problem and stopped them. Then, when asking vSphere to delete the VMs, all write I/O stalled. A bit too much irony for me :)
>
I've been trying to track down a similar stall/hang on 151a for several 
weeks.  I filed an Illumos bug on it, and I've been trying to debug this 
myself but I'm not having much luck.  Can you enable kmdb (boot with -k 
option) and force a crash dump when the IO stalls?  I'm curious to know 
if it looks like the same issue.

See http://www.illumos.org/issues/1618

Bryan