Insufficient speed with iSCSI DSS 6

[dalepbx]

After many hours of evaluation (ruling out everything else), I changed the virtualized testing OS form Windows XP to Server 2003.

With Server 2003 IOmeter measured ~90 MiB/s for a single GBe Link and ~195 MiB/s for MPIO, wich is not great, but more then sufficient.

However i have no clue if/why XP differs from 2003 concering iSCSI

[rascalwind]

Another thing to make sure is that your raid controller and drives are compatible. If the drives are not compatible with the raid controller you can have issues. There can be a large number of io ops waiting on drivers and response from disk. Turning off things like caching and tagged command queuing can drop performance significantly. The raid card driver may be doing this if it sees a problem with requests that are failing and piling up.

[icepicknz]

So I have a similar issue.

I have 4 bonded links in 802.3ad on my DSSv6 system with raid 6 configured on the 8 drives via the 3ware console.

I have tested across these bonded links to my 2 xenserver hosts and from within a VM I'm getting 200mb/s (mbits not bytes) write and 650mbits/s read, so not even using a full 1Gb link. To ensure there is no problem with the bonds or the switch I have another interface on my Dssv6 linked directly to one of my xenserver hosts and I get the same speeds. I've even tried to use mpio across the bond and the single ethernet and the speed remains the same.

Surely I should expect at least 1gb/s write / read minimum.
Disks are datacenter (I think they call them ES, but cant remember) 1TB 7200 sata drives capable of 3Gbps