Controller Performance

[Ayman Altounji]

We currently have 2 Proliants running in a Microsoft cluster using RA8000 storage enclosures with HSZ70 SCSI controllers as shared storage.

I have been looking into the possibilty of moving the shared storage to fibre using a fibre hub 7 and 64-bit/66Mhz Fibre Channel Host Adapter.

I am unsure whether this hardware set-up will be as quick as the existing one.

Any help would be greatly appreciated.

Thanks in advance.

[Ayman Altounji]

Can't vouch for you're particular configuration but in my experience fibre attached storage is not as quick as SCSI, although fibre obviously gives better scalability.

Also am I right in saying that you would need to change you're HSZ70's for fibre one's (HSG80's presumably)?

[Ayman Altounji]

Thanks for the reply.

We are considering replacing our HSZ70 controllers that are connected to 2 x RA8000 storage arrays via Adaptec SCSI controllers, to a solution which uses Compaq Fibre storage hub 7s connecting 2 x 4100 storage arrays via 64-bit/66Mhz Fibre Channel host adapters.

[Ayman Altounji]

My initial thought is that you will take a hit on performance, at the moment you're arrays are spread over 6 SCSI channels in the RA8000 (presuming they're set up that way) thus maximizing your I throughput. In the 4100's you only have one SCSI channel for all disks in the enclosure, you can't load balance between the two enclosures for the same array either.

I recently migrated our customer database (SOL 2000) from two RA4100's fibre attached though a Hub 7, to an MA8000 solution using the HSG80 controllers etc. Heavy I operations that used to take 2hrs now take 1/2hr, admittedly it's also been moved onto a faster server but the operations are highly dependant on disk IO.