Iscsi performance problem.

[Robstarusa]

Hello everyone!

I recently setup freenas with NFS & Iscsi.
For the nfs part I have 10 * 500G in a raid10. Performance is pretty good.

For the iscsi setup I have 4 * 60G OCZ agility (brand new, latest firmware) on an ibm serveraid controller. I'm using them individually right now. The OS is freenas (freebsd...). I have configured the vm host with iscsi + lvm.

With NFS I can max out gigabit ethernet. Talking to a single SSD, I can't break 7MB/second..!! My test is a "qmrestore" from a backup from NFS to an "lvm" storage target that sits on top of iscsi.

The VM host has dual bonded gigabit ethernet.
The Freenas box has a single gigabit ethernet.

Any ideas on what I should be looking at?

An iostat -x <something> shows the iscsi lun as 100% utilized on the vm host.

 

[udo]

Hi,
do you use the same lan for normal networking and iscsi?. Perhaps it's better to cancel the bond and use one nic for the network and one nic for iscsi-traffic.
For Iscsi it's goot to use a bigger mtu (9000).
Look before for the network-performance with iperf - try with both bond-paths and perhaps only with one path. Can you change the switch between proxmox and freenas? Or use for testing a direct cable?

Udo

 

[whinpo]

Hi,
do you use the same lan for normal networking and iscsi?. Perhaps it's better to cancel the bond and use one nic for the network and one nic for iscsi-traffic.
For Iscsi it's goot to use a bigger mtu (9000).
Look before for the network-performance with iperf - try with both bond-paths and perhaps only with one path. Can you change the switch between proxmox and freenas? Or use for testing a direct cable?

Udo

The MTU900 isn't always a good idea...i had perfs troubles because of this MTU9000...

after having disabled it (on switches, NIC and so on) everything ran fine...