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RE: Large PGA for a data warehouse on Windows 2003 advanced server(32 bit)

From: Jeffrey Beckstrom <>
Date: Thu, 28 Jul 2005 12:41:44 -0400
Message-Id: <>

Don't forget to account for at least 500M for the buffer window used to map the indirect buffers.

>>> "Allen, Brandon" <> 7/28/05 12:27:11 PM


See Metalink Note 1036312.6 for info on how to use up to 3GB (set /3GB switch in your boot.ini) or see note 46001.1 for info on how to use more than 3GB (for buffer cache only - you have to set USE_INDIRECT_DATA_BUFFERS=true, and then use the old, static db_block_buffers instead of new, dynamic db_cache_size - and can't use db_cache_advice either). So, theoretically, I believe you could use 1GB for Windows, 3GB for your PGA/SGA and then use the remaining 28GB for your buffer cache. I don't think there is anyway to allocate 4-6gb for PGA on Windows, but maybe someone else will have an idea. Have you opened a TAR?

I've used the 3GB switch a few times with no problems, but have never used the second method for accessing > 3GB. If you try it, please let me know how it goes.


-----Original Message-----
[]On Behalf Of Ken Naim Sent: Thursday, July 28, 2005 9:15 AM
Subject: Large PGA for a data warehouse on Windows 2003 advanced server(32 bit)

Dear List,

I am developing a data warehouse using Oracle 10g R1 on Windows 2003 advanced server(32 bit). The server has 32gb of ram and ideally I'd like to allocate a good portion of it to the pga and not just db block buffers. As I understand it windows "sees" 4gb of ram, 2gb of which is for windows, 1gb which is used for db block buffers which can map to higher regions of memory for larger amounts of db block buffers, leaving only 1gb of memory for the sga and pga. I'd like to know if there is a way to use more of the ram for the pga, in the neighborhood of 4-6gb.

My background is on the unix side, so please keep the switch to linux comments to a minimum. I do not have a choice in this matter.


Ken Naim

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Received on Thu Jul 28 2005 - 11:46:48 CDT

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