ZFS on top of GELI / Intel Atom 330 system

[Chris Dillon]

Quoting Dan Naumov <dan.naumov at gmail.com>:

> Ouch, that does indeed sounds quite slow, especially considering that
> a dual core Athlon 6400 is pretty fast CPU. Have you done any
> comparison benchmarks between UFS2 with Softupdates and ZFS on the
> same system? What are the read/write numbers like? Have you done any
> investigating regarding possible causes of ZFS working so slow on your
> system? Just wondering if its an ATA chipset problem, a drive problem,
> a ZFS problem or what...

I recently built a home NAS box on an Intel Atom 330 system (MSI Wind  
Nettop 100) with 2GB RAM and two WD Green 1TB (WD10EADS) drives in a  
mirrored ZFS pool using a FreeNAS 0.7 64-bit daily build.  I only see  
25-50MB/sec via Samba from my XP64 client, but in my experience SMB  
always seems to have horrible performance no matter what kind of  
servers and clients are used.  However, dd shows a different set of  
figures:

nas:/mnt/tank/scratch# dd if=/dev/zero of=zero.file bs=1M count=4000
4000+0 records in
4000+0 records out
4194304000 bytes transferred in 61.532492 secs (68164052 bytes/sec)

nas:/mnt/tank/scratch# dd if=zero.file of=/dev/null bs=1M
4000+0 records in
4000+0 records out
4194304000 bytes transferred in 33.347020 secs (125777476 bytes/sec)

68MB/sec writes and 125MB/sec reads... very impressive for such a  
low-powered box, I think, and yes the drives are mirrored, not striped!