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RE: SGA/PGA question

From: <>
Date: Fri, 25 Aug 2006 16:49:11 -0400
Message-ID: <>

What are the commands to check the memory usage by each process on sun box, since sga is 600gb and pga 200gb and still we are seeing 0 free ram left so there must be other processes to check before I can change and of this parameters. I completely agree that we need bigger machine but still I need to solve this issue for 2-3 weeks.


-----Original Message-----

From: Bobak, Mark [] Sent: Friday, August 25, 2006 4:40 PM
To: Harvinder Singh; ORACLE-L
Subject: RE: SGA/PGA question

Hi Harvinder,

First off, there is no pga_target parameter. I'll assume you're referring to pga_aggregate_target. With it set to 200MB and expecting 900 dedicated server processes connecting concurrently, that's about 233017 bytes per server process for pga memory. That's WAY too small.

Assuming that you have 2GB RAM, and you're ok w/ the 600MB you've allocated to sga_target, well, perhaps you could try bumping pga_aggregate_target to 900MB. But, even there, you're only at 1MB per server process. Unless you have VERY MODEST memory usage requirements, that's not going to be enough.

You need a box with more memory. Shared server (aka MTS) is not a panacea.

Also, are you using raw devices? If you're on cooked filesystems, are you using direct I/O? If not, the OS will use memory to cache your datafiles in the filesystem layer, and consume memory there too.

Bottom line, you need more memory....



Mark J. Bobak
Senior Oracle Architect
ProQuest Information & Learning

Ours is the age that is proud of machines that can think and suspicious of men who try to. --H. Mumford Jones, 1892-1980

-----Original Message-----

[] On Behalf Of Harvinder Singh Sent: Friday, August 25, 2006 4:24 PM
Subject: SGA/PGA question


We have installed on sun solaris 10 having 2GB RAM and 2GB swap file. In our system 4-5 application starts at same time and each requires about 180 connections to the database. So about 900~ processes can be connected at the same time and we have set the following parameters:
Processes = 1000
Pga_target = 200MB
SGA_TARGET = 600MB We are using the dedicated server model and getting following error frequently and also notice that physical RAM drops to 0 MB free: Ora-12500 (unable to start the dedicated process)

Since this is just a development box, so to fix this issue we are planning to move to MTS model.

Is there any other way to solve this issue, if we have to go to the MTS model what should be the value of PGA and SGA to be set?



-- Received on Fri Aug 25 2006 - 15:49:11 CDT

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