Re: SGA Size

I don't know that SGA can expand as it needs to - that's news to me (OpenVMS, ORACLE7 V7.1) [ref: Gautam Das note]

ORACLE will use as much memory in it's SGA as you can give it - the more in memory the fewer times it goes to disk. It becomes a balance of OS paging/swapping overhead your user regions go though, and your hit ratios. For me, I try for a hit ratio as close to 100% as possible while keeping user paging to a minimum. At the moment I run a 256Meg SGA on a 1000Meg AS2100 for about 120+ online users. I pin large packages and CACHE tables under 1Meg. I am considering increasing the SGA even more.

Use your Bstat/Estat scripts to track your hit-ratio performance and adjust accordingly. Much depends on how much memory your machine has.

Wayne Linton Received on Sun Sep 08 1996 - 00:00:00 CEST