Questions about performance tuning rules of thumb

From: x <xenophon_at_usa.net>
Date: 1998/03/16
Message-ID: <6el18b$qqg$1@news.metrobbs.com>#1/1

We are looking into optimizing i/o performance for a data warehouse running Oracle 7.3.3 on HP/UX 10.3. Are these rules of thumb reasonable for warehouses?

1. The more memory the better. Oracle loves memory. Is there a relationship with lots of memory improving certain types of read performance for system tables? Should the SGA be set as large as possible? I hear this commonly in the AIX world.
2. Raid 1/0 for system, rollback, temp and high write tables. Raid 5 OK for mostly read tables. This sounds reasonable for a warehouse. Comments?
3. Oracle parallel does not like striping. Is this true? Parallel _server_ only? Are there some cases where mirroring should be used w/out striping?
4. Consider solid state disk for system/temp/rollback. Is it worth it? SSA? EMC?

What are some other things to look at... CPU performance is fine but I/O is a problem. The drives are configured like "rule" #2 using 80GB Nike drives but the SGA is only 500MB on a 1GB box.

Would increasing SGA help i/o performance for certain operations? What would 2GB RAM give you if the db runs reasonably well in 1GB but i/o could be improved?
Can you have too much memory - that does nothing for performance?

Thanks.. reply email as well if you can.

xenophon_at_usa.net
XenoTech Received on Mon Mar 16 1998 - 00:00:00 CST