Re: OS9 ext. for ATTO ExpressStripe?

Here's the scoop on ExpressRAID for OS 9 and ExpressStripe for OS X:

ExpressRAID v2.81 for OS 9 can create raid 0 and 1 raid volumes as well as standard (non-raid) volumes for use in OS 9. This application has been refined for maximum performance over many years and you should be seeing the maximum performance that your drives and your computer are capable of in OS 9. The application is OS 9 only.

ExpressStripe v1.2 for OS X can create raid 0 and standard (non-raid) volumes on OS X (ATTO has announced that it will be adding raid level 1 and 0+1 support in the future). These volumes can also be used in OS 9 with the OS 9 compatibility extension available for free download on our website (http://www.attotech.com). Also, installing ExpressStripe installs an extension into OS X that will allow you to use ExpressRaid (OS 9) formatted volumes (Raid 0 only) in OS X. The performance of OS 9 formatted volumes on OS X and OS X formatted volumes on OS 9 are almost the same as volumes that where created and used on the same platform.

Currently, raid performance on OS X is about 20% slower then OS 9. This is due to Apple's SCSI family drivers in the OS. Apple has re-written the driver and it has been included in OS X v10.2.x. However, there are two problems that need to be resolved before the performance benefits can be realized. 1) Apple needs to resolve some fundamental issues with the new drivers and 2) ATTO needs to develop drivers to support the new SCSI family. ATTO had committed to doing this, first on our UL4 cards and Fibre Channel cards then the rest of our line... However, we can not release this code until Apple resolves the issues with the new SCSI family drivers. When this happens, we expect to see performance that is at least on par with OS 9 and probably considerably better.

ATTO, Apple and Pinnacle are in constant contact, working together on resolving these issues...

-Victor Konshin
Application Engineer
ATTO Technology, Inc.