ASMM - resizing triggers/thresholds

From: Martin Klier - Performing Databases GmbH <martin.klier_at_performing-db.com>
Date: Thu, 31 Jan 2019 11:00:35 +0100 (CET)
Message-ID: <1788046197.6506.1548928835221.JavaMail.zimbra_at_performing-db.com>



Hi listers,

how and when are memory areas like DB cache and shared pool being resized, when the instance runs in Automatic Shared Memory Management?

In my case, I have a system that has had some shared pool eating (child cursor issue, blowing up the library cache), which was resolved. Now we have a de-facto undersized buffer cache and low library cache consumption, but I can't see any resizing taking place. I have SGA max size = SGA Target and no minimum values for any component here.

Platform: Linux, Oracle EE 12.2.0.1

It would not be a big problem to restart the instance at some point, but this may be different for other cases. So my interest is more educational. :) In short: Where are the thresholds, what does trigger the resizing, how often is it scanned, when does it happen?

Thanks in advance!
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Martin Klier // Performing Databases GmbH Managing Partner // Senior DB Consultant Oracle ACE Director

martin.klier_at_performing-db.com // https://www.performing-databases.com

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http://www.freelists.org/webpage/oracle-l Received on Thu Jan 31 2019 - 11:00:35 CET

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