Re: Determining Memory Allocations - Dedicated/Shared Server

On Jan 25, 12:50 am, "Dereck L. Dietz" <diet..._at_ameritech.net> wrote:
> I've found "formulas" for determining the SGA/PGA sizing for a dedicated
> server.
>
> Using a formula from  the Burleson Consulting web site I was able to come up
> with these figures:
>
>                                                           --  8 GB --   --  
> 16 GB --    -- 32 GB --
> Total RAM on Windows Server         8,191.0 MB 16,384.0 MB 32,767.0 MB
>
>  Less:
>
>  Total PGA regions for 100 users        3,980.0 MB  3,980.0 MB  3,980.0 MB
>
>  RAM reserved for Windows (20%)   1,638.2 MB  3,276.8 MB  6,553.4 MB
>
>  RAM for SGA & Buffers                   2,572.8 MB  9,127.2 MB 22,233.6 MB
>
> What I've been trying to find out is how would I determine the memory
> allocations if both dedicated and shared connections would be in use?  Is
> the memory allocated for a shared server configuration, a dedicated server
> configuration or is there a "hybrid" server configuration that's used?

If these formulas come from Burleson Consulting, they are probably new Silver Bullets and new generalizations.
Burleson always comes up with 'formulas', 'silver bullets' and usually they just don't work.
Apart from that: whether a larger SGA has any positive impact is largely determined by the application.
If the application randomly selects data, bumping up the SGA is not going to help, ever.
Most 'savvy professionals' (favorite catch phrase of Burleson) are aware of this, only Burleson continues to spread myth, fairytales and formulas.

--
Sybrand Bakker
Senior Oracle DBA