CIFS very slow on PowerEdge 2950

[Cwhitmore]

I have a Dell PowerEdge 2950 (dual Xeon 2Ghz 5130), with (6) 73GB 10k SAS drives. I've set them up with RAID-5 onboard, I've tried to set them up as inidividual volumes onboard and then used ZFS (RAIDZ), and tried using UFS. I get the same write speeds (10-12mb/s).

There is 4GB of RAM in the server and I know everyone is recommending 6GB min., but when I check the reporting during the file copy test it's using less than 2GB at all times. I'm using one of the built in GB NICs (broadcom or Intel).

I'm running the latest build that I downloaded today, 8.0.1-RC2-amd64 (7813).
Is this server just too old to take advantage of ZFS?

 

[Milhouse]

Yes, your system should be fine for ZFS. Of course more memory would be nice, and unless/until you can add more RAM you might want to consider enabling ZFS read prefetch by adding vfs.zfs.prefetch_disable=0 in /boot/loader.conf and rebooting (this option is automatically disabled on systems with 4GB or less RAM, but can significantly improve read performance, not your immediate problem I realise).

I'd start by checking that your network is operating normally - try a test with iperf to make sure there are no problems there.

Also, some basic dd commands (dd if=/dev/zero of=/mnt/tank/zero.dat bs=1M count=8000, dd if=/mnt/tank/zero.dat of=/dev/null bs=1M etc.) would help determine if the performance of your disk subsystem is up to snuff.

There are some CIFS-specific performance settings in Services->CIFS, eg. Large RW support, Send files with sendfile(2) and Enable AIO that you should enable.

 

[Cwhitmore]

Milhouse,
Thanks for the suggestions. In addition to your settings I enabled jumbo frames on both ends and moved FreeNAS and client to same switch.

I'm now getting over 100mb/s write speeds.

 

[Milhouse]

Nice. Glad I could help. :)