Low Hit Ratio

Hi ,

Oracle Version 8.1.7 on HP-UX 11 with 4GB RAM & 3 CPU's (540MHz). Machine Hosts Oracle Apps 11i & Database Server as well.

Current settinngs in init.ora are :

DB_BLOCK_BUFFERS 80000
DB_BLOCK_SIZE 8192
Shared_pool_size 382 MB
Log_Buffer_size 10MB
processes 750
open cursors 900
session cached cursors 900
log_checkpoint_interval 100000
sort_area_size 1024000
db_writer_processes 3
dbwr_io_slaves 3
timed_statistics true
cursor_space_for_time TRUE

Current database size is around 48GB & database is in NOARCHIVELOG mode.

We are experiencing low cache hit ratio like 60% in peak hours i.e. when users fire lot many reports.

I wish to know if I have some room to increase DB_BLOCK_BUFFERS. 625 MB SGA for 48GB DB seems low . But I want to know till how much can i raise it ? Since no of processes are ard 750, how much memory do they take in all ?

Any advise on this is kindly appreciated ....

Regards ,
Mahesh Hardikar Received on Thu Jan 09 2003 - 09:23:44 CET