Re: 9i's dynamic sga

does this apply to all platforms?

cheers

Howard J. Rogers wrote:

> Yup.
>
> Set SGA_MAX_SIZE to X, and Oracle nabs the whole of X from the O/S, even if
> then doesn't go on to allocate all of X to the various components of the
> SGA. The 'show SGA' command then displays what has been reserved, not what
> is actually in use (which is a shame, I think, but you leanr to live with
> these things).
>
> It has to be this way (the reserving, not the displaying), because when you
> dynamically increase the buffer cache or shared_pool, the granule
> allocations have to be contiguous allocations of memory -contiguous, that
> is, with what was already there.
>
> Regards
> HJR
>
>
> "sg" <s4v4g3_at_europe.com> wrote in message
> news:3D14FFD2.2040303_at_europe.com...
>

>>Does anyone know if no matter how we set the shared pool and db cache
>>Oracle's memory consumption at OS level will always equal to
>>sga_max_size? I set a pretty low db cache and shared pool and a large
>>sga_max_size and when I do show sga it actually syas that the
>>sga_max_size sga is allocated. Does Oracle reserve sga_max_size memory
>>at OS level since instance startup?
>>
>>