Re: Oracle on NT4 memory use

"Holger Knust" <knusth_at_bellsouth.net> wrote in message news:<TZOMa.6103$Sy1.3837_at_fe02.atl2.webusenet.com>...
> We upgraded a server from 512MB to 2.5GB due to performance issues. The
> server still uses ca. 512MB of physical memory. The total commit charge is
> 1.8GB. Physical Memory available is about 2GB.
>
> I've read about NT's 2GB/2GB problem, but I am not sure whether that is the
> cause.
>
> The main problem are most likely inefficient queries, but I would like to
> maximize Oracle's memory use in the mean time. If I see 2GB of RAM free, I
> would like to put them to use.
>
> Any ideas?
>
> Thanks,
>
> Holger

You won't be able to use the 2G. By design NT uses 50 percent of the memory for O/S purposes. Hence Oracle recommends to use only 1/3 of physical memory for the SGA. See the relevant documents on NT architecture on Metalink.
You should address the root cause instead of fighting symptoms. Generally speaking increasing the size of the SGA also increases paging and swapping. All Oracle hitratio's 99 percent and your OS will be suffocating.

Sybrand Bakker
Senior Oracle DBA Received on Thu Jul 03 2003 - 11:58:50 CEST