H163649:  PERFORMANCE ENHANCEMENTS FOR SERVERAID I AND II ADAPTERS


 TEXT:
 SYMPTOMS:

 Slow performance of the ServeRAID I and II Disk subsystem.

 FIX:

 Performance enhancements for the ServeRAID I Adapter,
 ServeRAID II Adapter, and ServeRAID II Onboard Controller
 can be achieved (and not limited to) as follows:

 1- The "IBM ServeRAID and ServeRAID II BIOS Flash Diskette
    version 2.70 and later"* offers several performance
    enhancements for RAID Levels 1, and 5 on the
    ServeRAID II Adapter.

 2- Changing the Write Policy to Write-Back Mode will improve
    performance for RAID Levels 0, 1, and 5 with RAID 5 yielding
    the greatest performance of the ServeRAID II Adapter
    / Controller.

    Adjustment of the Write Policy will improve performance for
    RAID Levels 0, 1, and 5 on the ServeRAID I and ServeRAID II
    Controller.

 3- Selecting the optimum Stripe Unit size with respect to the
    System I/O Request will maximize overall performance of the
    ServeRAID I and ServeRAID II Controller.

 Note: The Users Guide that shipped with the System or Option
 as well as the HMM (Hardware Maintenance Manual) for the System
 lists existing ways (to include item 2 and 3 above) to increase
 performance of the ServeRAID I and ServeRAID II Adapters and the
 Onboard ServeRAID II Controller.

 Refer to the HMM (Hardware Maintenance Manual) p/n10L9147,
 publication S10L-9147-00 for additional information on the
 ServeRAID I and ServeRAID II Controller.

 *Note: The "IBM ServeRAID and ServeRAID II BIOS and Flash
  diskette version 2.70 or later" is available at the IBM Web
  Site at the following URL:

          http://www.pc.ibm.com/us/files.html

      - Select "Search"

      - Type "BIOS 2.70" in the keywords box
      - Select "Search"

      - Select the Readme file associated with the "IBM ServeRAID
        and ServeRAID II BIOS and Flash diskette version 2.70"

      - Print out the contents for directions to apply the BIOS
        update and Firmware Flash

      - Select the "IBM ServeRAID and ServeRAID II BIOS and Flash
        diskette version 2.70" to download (the diskette is a
        self-extracting executable file that will create a
        bootable diskette)

 
DATE: September 9, 1998