HEADS UP: New ZFS in the tree.

[Larry Rosenman]

On Wed, 19 Nov 2008, Jeremy Chadwick wrote:

>
> Since this is CURRENT, you should be able to increase the kmem_size
> and kmem_size_max entries to something larger than 1536M, especially
> since the box has 4GB of RAM.  (You shouldn't do this on RELENG_7).
>
> You might also consider disabling prefetch; there are reports of
> peoples' boxes locking up hard (requiring a hard reset) when prefetch
> is enabled.  Others (like myself) just see "better overall system
> responsiveness" when prefetch is disabled.
Just as a note, with a -CURRENT from shortly after the ZFS upgrade, 
the vm.kmem* tuneables, without ANY override on my 4G amd64 box:

vm.kmem_size_scale: 3
vm.kmem_size_max: 4509713203
vm.kmem_size_min: 0
vm.kmem_size: 1381195776

this is with a 2T zfs array, if that matters.


-- 
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 512-248-2683                 E-Mail: ler at lerctr.org
US Mail: 430 Valona Loop, Round Rock, TX 78681-3893