Still getting kmem exhausted panic

Andriy Gapon avg at
Wed Sep 29 07:25:10 UTC 2010

on 29/09/2010 03:38 Artem Belevich said the following:
> On Tue, Sep 28, 2010 at 3:22 PM, Andriy Gapon <avg at> wrote:
>> BTW, have you seen my posts about UMA and ZFS on hackers@ ?
>> I found it advantageous to use UMA for ZFS I/O buffers, but only after reducing
>> size of per-CPU caches for the zones with large-sized items.
>> I further modified the code in my local tree to completely disable per-CPU
>> caches for items > 32KB.
> Do you have updated patch disabling per-cpu caches for large items?
> I've just rebuilt FreeBSD-8 with your uma-2.diff (it needed r209050
> from -head to compile) and so far things look good. I'll re-enable UMA
> for ZFS and see how it flies in a couple of days.

I've just uploaded uma-3.diff.
It implements what uma-1.diff did, plus totally skips per-CPU caches for items >
32KB, and also has code from uma-2.diff for flushing per-CPU caches on
significant memory shortage.

Will appreciate your feedback.
Thank you for testing!

Andriy Gapon

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