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Re: PGA allocation

From: Mladen Gogala <>
Date: Sat, 17 May 2003 12:06:59 -0800
Message-ID: <>

Ashish, your setting for the PGA_AGGREGATE_TARGET is far too big. For an OLTP system it is recommended that this parameter is 20% of the SGA size and of a DSS system, the recommendation is 50%. What is happening in your case is very simple: the maximum memory for PGA an never be reached, so the instance doesn't release it. Take a look at the Metablink Note:223730.1

On 2003.05.17 12:41 Ashish wrote:
> Hi
> I am facing a problem regarding PGA allocation. In the database on
> Windows 2000,
> PGA_AGGREGATE_TARGET is set to 1G, SGA is 1G. The database server has 4 GB
> physical memory plus
> virtual disk space. The front-end is written using ASP. The web server
> connects to the database using
> connection pooling.
> The problem is, the PGA allocation to sessions gradually increases over the
> time then it reaches
> memory limit on the server and web-server connections fail with ORA-04030
> error (out of process memory).
> (The PGA allocation/per session can be seen using V$PROCESS view and total
> PGA allocation can be seen
> using V$PGASTAT)
> I am not able find out why the PGA is not getting released. I do not see any
> continuously active sessions
> or huge sorts or anything that requires huge PGA. The PGA just keeps
> growing.
> Can anyone help me with this problem? Any help is appreciated.
> Also is there any way to peek into PGA and see how much is allocated to each
> session?
> Ashish

Mladen Gogala
Oracle DBA
Please see the official ORACLE-L FAQ:
Author: Mladen Gogala

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Received on Sat May 17 2003 - 15:06:59 CDT

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