Solaris 8 (SPARC Platform Edition) 10/00 Release Notes Update

Performance Issue

Direct Memory Access (DMA) Is Disabled On PCI-IDE Systems

By default, the Solaris ata device driver has the DMA feature disabled for ATA/ATAPI devices.

This feature has been disabled to avoid problems on some systems that do not properly support DMA on ATA/ATAPI drives. Most of the problems are related to an outdated system BIOS.

To enable (or disable) DMA for the ata driver after an installation of the Solaris 8 operating environment:

  1. Run the Solaris (Intel Platform Edition) Device Configuration Assistant from the boot diskette or the installation CD (if your system supports CD-ROM booting).

    Note -

    When booting with the boot diskette, the new ata-dma-enabled property value will be preserved on the diskette. Therefore, the changed value is in effect when reusing the boot diskette.

  2. Press F2_Continue to scan for devices.

  3. Press F2_Continue to display a list of boot devices.

  4. Press F4_Boot Tasks, select View/Edit Property Settings, and press F2_Continue.

  5. Change the value of the ata-dma-enabled property to 1 to enable DMA (a value of 0 disables DMA):

    1. Select the ata-dma-enabled property from the list and press F3_Change.

    2. Type 1 and press F2_Continue to enable (type 0 and press F2_Continue to disable).

    3. Press F2_Back, then F3_Back to return to the Boot Solaris menu.

    4. Select the device from which you want to install (network adapter or CD-ROM drive) and press F2_Continue.

    Note -

    If any problems occur after enabling DMA, disable DMA (set the ata-dma-enabled property to 0 using the above procedure), update your system with the latest BIOS from your hardware manufacturer, and then re-enable DMA.