This is tricky, and is really something that develops over time, as you
monitor the database performance and get an idea for where performance
suffers and what SGA components need tweaking. I don't think there are
any (valid) rules of thumb that can be applied. It would probably be
reasonable to use the ASMM sizes as a starting point. Then, monitor the
system. Look for any performance problems cropping up in your business
processes. If you see something not performing well, profile it. Use
that profile to tune, and to tell you where you need more resources in
your SGA allocation.
Mark J. Bobak
Senior Oracle Architect
"There are 10 types of people in the world: Those who understand
binary, and those who don't."
Sent: Monday, May 07, 2007 12:17 PM
Subject: SGA rules of thumb?
I'm wondering if any of you have general "rules of thumb" when it comes
to sizing the various pools and db buffer cache within the SGA.
I'm going to go back to static SGA rather than risk ASMM thrashing about
and causing another ORA-00600
at 2:30 in the morning. I can see where
ASMM left the sizes at last, but just wondering what human thinks of
This is Oracle 10.2.0.2 on RHEL3. sga_max_size is 1456M on 32-bit,
going to be (at least) 8192M on 64-bit. The database is a hybrid of
OLTP and warehouse. When I say "warehouse", I mean that large
partitioned tables holding millions of records exist, and are bulk
loaded via external tables and data pump throughout the day. Other than
the bulk loading, those tables are read-only.
Any advice would be appreciated (yes I've checked the V$*_ADVICE views
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