Buffer cache hits %

From: Kevin Gillins <kevin_gillins_at_compuserve.com>
Date: Thu, 15 Jul 1999 08:00:58 -0400
Message-ID: <O41ialrz#GA.309@nih2naae.prod2.compuserve.com>

I have a question about the buffer cache hits ratio we are experiencing.

We are on 7.3.3.5 database using 10.7 oracle apps most all products. Apx 100+ users.
The database size is apx 40 gig. We are on HP 4 processors with 2.5 gig memory.
There are 2 instances both the same size (prod and test). The shared pool is set
at 250,000,000 running 6 db writers. The production instance is on EMC disks.

My main question is the buffer cache hit% is sitting at 90% in general. Is this good, bad or
real bad. I want to get a feel. I have tried increasing the shared pool and db_block_buffers.

What other settings if any would improve this statistic. What stats could I check to see
what contributes to the 10% miss?

Your suggestions and answers are appreciated.

Kevin Gillins
Management Information Consulting
Boston Office
978-887-3300 Received on Thu Jul 15 1999 - 07:00:58 CDT