Pointer to info on migrating from UFS2 -> ZFS?

[David Wolfskill]

I appreciate the responses, but I seem to have failed to communicate at
least a couple of fairly important aspects of what I'm trying to do.
So....

On Mon, Apr 21, 2014 at 06:40:05PM -0700, Louis Kowolowski wrote:
> I?d probably suggest a couple things:
> * VirtualBox (or equiv) for setting up test environments that are easy to create and destroy. For all the beginning stuff I can think of, you should be able to do just fine with a virtual environment. VMs with a half dozen virtual disks that are 2G ea come in handy with playing with ZFS.

I have existing hardware -- several instantiations of it, including a
couple of test machines.  I am trying to find out if the use of ZFS (vs.
UFS2+SU) on the existing hardware will provide a performance advantage
(and if so, how much, as switching from UFS2 to ZFS is going to be
extremely painful).

> ...

On Tue, Apr 22, 2014 at 12:03:05PM +0800, Julian Elischer wrote:
> ...
> my experience so far is that ZFS is great if you want to do 'storage 
> things' but that for
> straight out speed you might want to stick with ufs+SU.
> ....

I appreciate that information, but I tend to be rather ... empirical ...
about this kind of thing.  Further, one of our colleagues was
practically begging me to test ZFS, citing VFS lock contention as an
observed bottleneck in the UFS2 case.

Therefore, my intent is to try to set up a reasonably plausible ZFS
environment -- to the extent that I am able -- using the existing
hardware, and measure the workload in question (several times) in each
environment.  (I may change aspects of the configuration: for example,
the UFS2 file system in question resides on a RAID 5 array of 10
spindles of 2TB each, using the "hardware RAID" capabilities of the
controller.  I understand that ZFS is better-suited to an environment in
which the controller does as little as possible, so I would set that up
and an N-spindle JBOD for ZFS.  What to do about teh ARC is less clear
to me -- as a specific case in point.)

Peace,
david
-- 
David H. Wolfskill				david at catwhisker.org
Taliban: Evil cowards with guns afraid of truth from a 14-year old girl.

See http://www.catwhisker.org/~david/publickey.gpg for my public key.
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