Hi Frndz,

Does MPHA make any improvement in loop performance....?

Also ,does the redundant primary path is been used for data flow...?

Please clarify



Filer distributes active paths to disk across two available paths. For Fibre Channel this happens per disk; for SAS this happens per shelf (at least, that is what I have observed).

There is no absolute answer to any performance question. MP-HA distributes IO across more HBAs; OTOH now you have two controllers competing for the same FC loop. This is less relevant for SAS. But I am sure that you will be disk and/or CPU bound long before you will be HBA bound.


Even with 4gb fc we didn't see back end bottlenecks with 2x4gb paths to esh4... Now with with 3 and 6gb sas. 4 lanes of 3 or 6gb for 12gb or 24gb per path. Then multipath and have 24gb or 48gb to the stack. I haven't seen a case where the back end is a bottleneck.