8.1R ZFS almost locking up system

[Tim Bishop]

On Tue, Aug 24, 2010 at 06:49:23AM +1000, Peter Jeremy wrote:
> On 2010-Aug-21 23:04:35 +0100, Tim Bishop <tim at bishnet.net> wrote:
> >I've had a problem on a FreeBSD 8.1R system for a few weeks. It seems
> >that ZFS gets in to an almost unresponsive state. Last time it did it
> >(two weeks ago) I couldn't even log in, although the system was up, this
> >time I could manage a reboot but couldn't stop any applications (they
> >were likely hanging on I/O).
> 
> Unless you have a ZFS-only system, it's possible you are running out
> of free memory (see the "free" entry in top(1) or 'systat -v') - in
> which case r211581 (and r211599 which fixes a mismerge) should help.
> Your very high kstat.zfs.misc.arcstats.memory_throttle_count suggests
> this is your problem.

Thanks. At the time I had a reasonable amount free (~450MB from 3GB),
but it had dropped lower than that at some points previously.

I'll take a closer look at that next time, and look at that patch (or
upgrade to 8-STABLE).

And the system has a UFS root, but all the apps/data are stored in ZFS.

Tim.

-- 
Tim Bishop
http://www.bishnet.net/tim/
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