FATA v FCAL disks

[grahame lancaster]

Hi,
we are having read latency problems with a ESX VM file server (connected to an HP EVA 8000).

The LUN is a 1TB FATA (with 500GB 7,200 rpm disks)

We have been told to use FCAL disks

Other than the spin speed are there any differences (eg. in sequential or random seek methods etc.)

P.S. This thread has been moevd from Disk to Storage Area Networks (SAN) (Enterprise). - Hp forum moderator

[Sameer_Nirmal · Accepted solution]

This document will be a good reference to find answer to your query.

ftp://ftp.compaq.com/pub/products/storageworks/whitepapers/5982-7353EN.pdf

[Uwe Zessin]

I have not looked at the specs, but am sure the FATA-L disk drives are slower on seeks as well. You should also check the firmware level of the disks - there is a strange bug that causes a read-after-write if the temperature gets 'too low'.

(by the way: FATA-L disk drives use the FC_AL protocol as well)

[grahame lancaster]

cheers for help guys - that doc is just what I was looking for