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Re: Oracle 10g on Windows 2003 x64 Memory Useage

From: <>
Date: Fri, 10 Aug 2007 00:00:59 -0700
Message-ID: <>

On Aug 3, 9:09 pm, Charles Hooper <> wrote:
> On Aug 2, 9:22 am, wrote:
> > Hi All,
> > We are running Oracle 10g on a Quad Dual Core Windows 2003 x64
> > Enterprise Server with 16GB of memory. I notice that the Oracle
> > process is only using 4.6 GB of Physical RAM and 10GB of Virtual
> > memory. Performance monitor is showing that the server has 8GB
> > Physical Memory free. This seems like oracle isn't using the free
> > memory very efficiently and swapping a lot out to disk, is this
> > something that can be tuned to boost performance or is it dynamically
> > performed by the Oracle process?
> > Thanks for your help, I'm new to Oracle having worked mainly with MS
> > SQL so go easy on me,
> > Regards,
> > Stephen
> Have you enabled large page support on Windows and Oracle, which
> causes Windows to use 4MB memory page sizes rather than 4KB memory
> pages? If so, I suspect that Performance Monitor is showing incorrect
> information. I am running Oracle on Windows 2003 x64, total
> page file size for all drives is configured at 3124MB, yet Task
> Manager reports that PF usage is 13.3GB. In my case, system
> performance is great, so I am not too concerned about the inconsistent
> numbers.
> Have you verified that the page file is actually 10GB in size?
> Charles Hooper
> IT Manager/Oracle DBA
> K&M Machine-Fabricating, Inc.

Apart from that useful bit of advice, be warned that 64-bit Oracle on 64-bit Windows 2003 that runs on AMD processors will experience a massive performance hit as memory starts paging maniacally once total memory consumption hits about 12.8GB. It's a known bug, there's a TAR out on it, it's allegedly fixed in (not yet tested, however), and it only affects AMD processor platforms.

Might not have any relevance to the OP, but I thought I'd mention it just in case... Received on Fri Aug 10 2007 - 02:00:59 CDT

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