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RE: Question about enabling Automatic Shared Memory Management

From: John Dunn <JDunn_at_sefas.com>
Date: Fri, 10 Aug 2007 12:32:20 +0100
Message-ID: <2F802216565E44489600A03F763219A828A3DC@mia.SEFASBRISTOL>


<<If you have a limited memory budget (However you want to read it), dont use asmm. Oracle will continue try to reallocate the available memory and bring your system to a screeching halt>>    

But presumably if you set sga_max_size, it will only try to use up to that value?    

John


From: Andrew Kerber [mailto:andrew.kerber_at_gmail.com] Sent: 10 August 2007 12:28
To: John Dunn
Subject: Re: Question about enabling Automatic Shared Memory Management

I dont know about about setting the shared pool size, but there is 1 key point that they completely miss in all the docs about asmm. That is, it only works well on systems with plenty of memory to allocate. If you have a limited memory budget (However you want to read it), dont use asmm. Oracle will continue try to reallocate the available memory and bring your system to a screeching halt.

On 8/10/07, John Dunn <JDunn_at_sefas.com> wrote:

        Platform is Oracle 10.          

        I thought that ASMM was enabled by setting sga_target to a non-zero value.          

        But I recently read the notes below, which confused me.          

        Do I really need to set shared_pool_size to a non-zero value? I thought the whole point of ASMM was that oracle calculated shared_pool_size?                    

        Oracle Automatic Shared Memory Management is enabled by setting:

        John Dunn

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Andrew W. Kerber

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Received on Fri Aug 10 2007 - 06:32:20 CDT

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