Using DSS as a Fibre SAN: performance tweaks

[Robotbeat]

There's no "file-io" and "block-io" settings when making a fibre channel volume. There's an "initialize," so perhaps it's like file-io, but whatever. There's a place where you select what block size to use (512B, 1024B, 2048B, or 4096B) and whether you want volume replication. I'm assuming that 4096B would be the best setting, usually, right? (Unless you're writing really tiny pieces of data, like with a database...)

What are the other options that I should be aware of? (Keep in mind that this is fibre channel, not iscsi)

Also, is it reasonable to expect a little higher throughput with fibrechannel (given the same linespeed) since there isn't the tcp/ip overhead?

We are planning to use build 3278, unless you recommend the Atlanta version for any good reason.

[To-M]

4096B would be best for Microsoft and use 512 block size for VMware as it does not support different block size.

Sometimes the iSCSI MPIO can get close but overall the FC provides better performance.

There is someone on the forum who has done some test.

http://forum.open-e.com/showthread.php?t=557

[jmo]

4096B would be best for Microsoft and use 512 block size for VMware as it does not support different block size.

Just for completeness, for others browsing this thread in the future: If running Xen servers, go for 512B blocks - your VMs will bail out otherwise.

Regards,
Jens