ZFS hanging

[Dennis Glatting]

On Fri, 2012-07-13 at 12:19 +0300, Volodymyr Kostyrko wrote:
> Dennis Glatting wrote:
> > I have a ZFS array of disks where the system simply stops as if forever
> > blocked by some IO mutex. This happens often and the following is the
> > output of top:
> 
> Try switching to clang. Some time ago I was hit by different error - 
> some process hangs indefinitely and can't be killed. After building 
> system with clang I obtained a core dump at first reboot and research 
> turned out that there was some broken directory entry in file system. 
> Recreating damaged zfs filesystem (leaving all other pool intact) solved 
> my problem completely.
> 

I am using clang except on my CVS mirrors.

I found on the mirrors that the mirror itself cannot update from itself
but other hosts can update from the mirror. Somewhere in that
M3/assembly muck something crashes in the process. The only way around
the problem is to compile the /OS/ using GCC.

On the system in question(iirc) I rebuilt the pool yesterday -- I'm in
the process of updating parts across my systems. I also wanted to fool
around with different ZFS architectures. This morning, with a load
average throughout the night of 42 on a 32 core system writing 4TB of
data, it is still alive and kicking but its early in the run.