[OpenIndiana-discuss] ZFS read speed(iSCSI)

[Heinrich van Riel]

Any pointers around iSCSI performance focused on read speed? Did not find
much.

I have 2 x rz2 of 10x 3TB NL-SAS each in the pool. The OI server has 4
interfaces configured to the switch in LACP, mtu=9000. The switch (jumbo
enabled) shows all interfaces are active in the port channel. How can I can
verify it on the OI side? dladm shows that it is active mode

The Hyper-v systems has 2 interfaces in LACP and all show as active and
windows indicate 2Gbps, never go over 54% util.

When I copy to an iSCSI disk from a local disk, it copies at around 200MB/s
and thats fine. When I copy from the iSCSI disk to the local disk I get no
more that 80-90MB/s and that is after messing around with the TCP/IP
setting on Windows. Before the changes it was 47MB/s max. (copy from the
local disk to the local disk I get 107MB/s so that is not the issue)
VMware 5.0 will not get more than that either.

Even when I do a zfs send/recv is seems that reads are slower. I assume
this is the expected behavior.

It will run only VMs for lab and I have the follwoing questions:

           * With this type of workload load would there be a noticeable
improvement in by adding a cache disk?
              Looking at the OCZ Talos 2 SAS. Any feedback would be
appreciated before spending the $900 on the disk.

           * System has 2x 6core E5 2.4, 64GB mem; would compression help?

           * Would it make more sense to create the pool with mirror sets?
( Wanted to use the extra space for backups)

Thanks