> I've seen equal or lower I/O demands on my systems using ZFS compared
> to UFS. Something else may be amiss on this system.
>

Ultra 5's have IDE drives as standard, and there is an issue with ZFS
performance on SPARC systems with IDE. It's CR 6421427; I've been
running test binaries with a fix on my X1 for a couple of weeks and it's
pretty happy. Hopefully it'll be patched soon, this is the second time
somebody's posted about it in the past few days.

Dave