8.1-RELEASE: [zfs] [kmem] zfs destroy snapshot results in panic: kmem_map too small

Andriy Gapon avg at icyb.net.ua
Fri Sep 24 13:04:08 UTC 2010

on 24/09/2010 15:33 Jeremy Chadwick said the following:
> As for your questions under "Questions" -- yes you have to tune, no
> there aren't really "reliable guidelines" and I've been asking for such
> since ZFS came out for FreeBSD, but your values look fine.

I can't provide you "reliable" or "authoritative" guidelines, but I have an advice
which seems to work.

On amd64 set your vm.kmem_size to at least the amount of available memory that you
got, or even more (1.5x, 2x).
An easy way to do that (1x) is to set vm.kmem_size_scale="1".
In head this is already done automatically, MFC to stable/8 is expected.

As to arc_max/arc_min, set them based your needs according to general ZFS

Andriy Gapon

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