topic Re: Witch Replication Protocol has better performance? in Disk Enclosures

Witch Replication Protocol has better performance?

Luis J. Fernández — Tue, 01 Mar 2011 10:15:32 GMT

Two EVA8400 with FC SAN Switches with Port Channel configured with two ISL ports per switch.
With Protocol HP-FC (in order delivery) only one of the ISL ports in every port channel is used (active-pasive), but it is one round trip.
With Protocol HP-SCSI FCP (exchange delivery) both ISL ports in every Port channel are used (active-active), but is is two round trip.
Remote site is about 10KM far.
Wich protocol can have better performance?

Re: Witch Replication Protocol has better performance?

Sivaramakrishna_1 — Tue, 01 Mar 2011 16:47:38 GMT

Make sure that EVA with Latest XCS - 9534 and select HP-SCSI (Exchnage based routing) which is the better performace method.

I have confiured at one customer place with Async replicaiton and found good.

Re: Witch Replication Protocol has better performance?

Luis J. Fernández — Tue, 01 Mar 2011 17:23:10 GMT

Thanks for your answer.
This protocol option is only available from 09534000 and our EVAs have that version.
With Async mode, perhaps it is the better option, but we have Sync mode and so, every I/O has two round trips to acknowledgement operation.
So, I don't know if this time lost, having two round trips, is bigger than the time gained travelling for two ISL ports instead of only for one ISL port per fabric.
That is the question.