RAID controller caching effects on Oracle
DBAsupport.com Forums - Powered by vBulletin
Results 1 to 3 of 3

Thread: RAID controller caching effects on Oracle

  1. #1
    Join Date
    Apr 2001
    Posts
    257
    Are there any general rules in terms of whether the caching, read-ahead, and write-back features should be enabled/disabled on a RAID controller to maximize Oracle performance?

    Thanks,

  2. #2
    Join Date
    Feb 2000
    Location
    Singapore
    Posts
    1,758
    Always disable write-ahead cache for disks containining redo logs and archived logs.
    The data that Oracle thinks has been written to disk might be still in cache and not written to disk. There is possibility of losing data from cache (power failure, battery problem etc.)

    Sanjay

  3. #3
    Join Date
    Apr 2001
    Posts
    257
    Thanks, SANJAY_G.

    However, my controller's manual has two write policy options available:

    Write-back caching: the controller sends a data transfer completion signal to the host when the controller cache has received all the data in a transmission.

    Write-through caching: the controller sends a data transfer completion signal to the host when the disk subsystem has received all the data in a transmission.

    I think your write-ahead cache is the same as the write-back caching on my controller. Am I correct?

    Thanks,

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


Click Here to Expand Forum to Full Width