Re: SGA

In addition it all depends what your performance issue is.

suppose you find that statements aren't being found in the shared pool for reuse. this means one of two things

1. the shared pool is undersized.
2. your app doesn't use bind variables.

in case 1 you should boost the shared pool size. In case 2 boosting the shared pool size will cause oracle to spend longer searching through a larger memory structure for statements that aren't going to be there anyway!

--
Niall Litchfield
Oracle DBA
Audit Commission UK
*****************************************
Please include version and platform
and SQL where applicable
It makes life easier and increases the
likelihood of a good answer

******************************************
"Andrew Mobbs" <andrewm_at_chiark.greenend.org.uk> wrote in message
news:YPq*rdNyp_at_news.chiark.greenend.org.uk...


> Candido Dessanti  <termy_at_blunet.it> wrote:

> >xueyang wrote:

> >> One simple question, Is it the larger the size of SGA is, the better

> >> performance we get?

> >

> >

> >Increasing the SGA normally makes the things going faster or at least

> >going as before until the increase cause swap on the OS so the things

> >could go slower.

>

> If your entire database (or at least the data set being accessed by

> common queries) already fits in the buffer cache, making the buffer

> cache larger may slow you down since there is more management

> overhead.

>

> --

> Andrew Mobbs - http://www.chiark.greenend.org.uk/~andrewm/