Results 1 to 4 of 4
  1. #1
    Join Date
    May 2009

    Exclamation Unanswered: buffer cahe hit ratio

    hie guys my buffer cache hit ratio is very low around 53% how can i change this iam on oracle 9i database on solaris 10. i have allocated db_cache_size=400m and shared_pool_size=1000m and sga_max_size=1500m. Total physical RAM is 4000m. I need your help please

  2. #2
    Join Date
    Jun 2004
    Provided Answers: 1
    Google has been fixed & is working again

    "Results 1 - 10 of about 201,000 for buffer cache hit ratio"
    90% of users' problems can be resolved by punching them - the other 10% by switching off their PCs.

  3. #3
    Join Date
    Feb 2009
    What you need to understand is that a high buffer cache does not mean that your system is running efficiently.

    The best advice I can give based on the (total absence of) information that you provide is to run statspack for about 5-15 minutes during periods when the system is performing poorly, and to tune the queries that come at the top of the logical and physical reads section.

  4. #4
    Join Date
    Mar 2002
    Reading, UK
    I have to agree with what the previous posters said regarding the mis understanding of the importance of the buffer hit ratio. However your memory allocations do seem a bit unusual in that the shared pool is so large compared to your buffer cache. Also how big is your pga and is anything else running on your server as it looks like you could allocate more to Oracle otherwise.

    To get a rough idea of how much better it might perform with a larger cache look at v$db_cache_advice


Posting Permissions

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