Strange ZFS performance

[Mikle Krutov]

On Sun, Apr 04, 2010 at 11:18:45PM +0400, Mikle wrote:
> Hello, list!
> I've got some strange problem with one-disk zfs-pool: read/write performance for the files on the fs (dd if=/dev/zero of=/mountpoint/file bs=4M count=100) gives me only 2 MB/s, while reading from the disk (dd if=/dev/disk of=/dev/zero bs=4M count=100) gives me ~70MB/s. 
> pool is about 80% full; PC with the pool has 2GB of ram (1.5 of which is free); i've done no tuning in loader.conf and sysctl.conf for zfs. In dmesg there is no error-messages related to the disk (dmesg|grep ^ad12); s.m.a.r.t. seems OK.
> Some time ago disk was OK, nothing in software/hardware has changed from that day.
> Any ideas what could have happen to the disk?
> 
> Wbr,
Well, list, somehow after moving some important files (about 50GB) 
to other disk performance became OK. I did not get why it was so 
crappy, if anyone could give me any ideas - that would be great.
Everyone, thanks for the replies.


-- 
Wbr,
Krutov Mikle