slow ZFS on FreeBSD 8.1

[Freek van Hemert]

Hello everyone,

This is my first mail on the mailinglist and I very much appreciate this
option of getting some help.

I have a question regarding zfs on freebsd.
(I'm making a home server)
This afternoon I did a "zpool create data mirror ad4 ad6" Now I'm copying
things from my ufs2 disk into the 2TB zpool, it is very slow. I'm on freebsd
8.1 amd64 on an atom n330 with 2 sata disks, gstat tells me I'm going at
around 2 mbps at near 100  %busy while the ufs2 drives are near 0. Also,
ufs2 to ufs2 was much faster (I estimate about 10 times faster). How do I
tune? The wiki is not helpful for amd64 users stating that the defaults
should be optimal. I'm using the 8.1-stable version which has just been
installed this afternoon from a minimal install iso.

I'm copying from a single ufs2 pata drive into a sata zpool mirror. I have
2GB of ram.

Top tells me: 761 MB Active, 790 Inactive and there is hardly any cpu usage
(96-98% idle). vfs.numvnodes: around 12500 now (after several hours of
copying) and stil slowly rising.

Hope you can help me.

Freek
(from the Netherlands)