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RE: determine total memory used by Oracle via OS tools

From: Alvaro Jose Fernandez <>
Date: Wed, 15 Aug 2007 16:24:00 +0200
Message-ID: <>

Also (aside note), there are one bug in related to hash joins using excess memory (above pga_aggregate_target).  

I recommend getting a "snap" at peak time with the SQLAREAT tools from Carlos Sierra of Oracle (Note 238684.1) . This tool is great to detect improper PGA memory usage/bad plans.

Also a statspack snap would reveal if there's something wrong (multipass execs from the PGA report).  


 Álvaro Fernández
 Departamento de Sistemas_    

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De: [] En nombre de Greg Norris Enviado el: miércoles, 15 de agosto de 2007 15:53 Para: ORACLE-L
Asunto: determine total memory used by Oracle via OS tools  

I'm looking for a good way to determine total Oracle memory usage, taking shared memory into account, using standard Unix/Linux tools. I can, of course, easily determine how much memory the database is configured to use, but need something which indicates how much the OS has actually allocated. Any suggestions?

Here's a little background. We recently had an outage on one of our databases running under SunOS 5.10, for which our SysAdmin believes the root cause to be Oracle using all available virtual memory. I'm somewhat skeptical, however, since the problem didn't go away after shutting down the database (shutdown immediate) and listener...normal operation was restored only after rebooting the server. In addition, I've learned that he used the "prstat -t" command to make this determination, which doesn't distinguish between shared and non-shared memory (thereby grossly over-reporting the usage).

At this point we've opened a SR with Oracle to followup on the outage itself, but I need to be able to provide an alternate (useful) command for determining memory usage at the OS level next time this sort of thing comes up.


"I'm too sexy for my code." - Awk Sed Fred.


Received on Wed Aug 15 2007 - 09:24:00 CDT

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