Re: Need advice on ORA-04030 and pga_aggregate_target parameter

On 15 mai, 20:52, Ronny <nitely..._at_ist-einmalig.de> wrote:
> > Why would you say that? The Oracle rule is 40% of RAM.
>
> > The largest recommended would be 1.6GB.
>
> Example for OLTP systems: "... leaving 80% for the SGA."http://download-uk.oracle.com/docs/cd/B19306_01/server.102/b14211/mem...

Daniel and Ronny.. How could percentage of total RAM be a useful figure ?

On one hand, assume two GB of ram, and 500 MB of overhead for OS etc... Then maximum memory available to Oracle is 1.5 GB, or 75% of total RAM. Now add 2GB. Then memory available is 3.5 GB, or 87% of total RAM. Therefore, memory available to Oracle is not a fixed percentage of total RAM.

On the other hand, the memory required for a given performance level depends on a lot of factors, such as block working set, number of sessions, etc. These factors are mostly uncorrelated to total memory...

Therefore, neither available memory nor required memory is a fixed percentage of total memory..

• Raoul