Re: Thoughts on Linux, Oracle, and VLM
From: Tim Hall <tim_at_oracle-base.com>
Date: Sun, 22 Apr 2012 08:59:42 +0100
Message-ID: <CAP=5zEgdH-Du8on4Nmegispr5p+_6rAXug5-01LqpYwPwhEFJQ_at_mail.gmail.com>
I agree with Jared, that it depends on a number of factors, including the number of connections to the database. On a server with a single Oracle instance (and no other software running) I usually suggest a starting point of 70-80% of physical memory being allocated to the instance. From that point on you have to monitor and adjust accordingly until you hit your sweet spot. The aim being to allocate the maximum memory possible without going into swap.
Date: Sun, 22 Apr 2012 08:59:42 +0100
Message-ID: <CAP=5zEgdH-Du8on4Nmegispr5p+_6rAXug5-01LqpYwPwhEFJQ_at_mail.gmail.com>
I agree with Jared, that it depends on a number of factors, including the number of connections to the database. On a server with a single Oracle instance (and no other software running) I usually suggest a starting point of 70-80% of physical memory being allocated to the instance. From that point on you have to monitor and adjust accordingly until you hit your sweet spot. The aim being to allocate the maximum memory possible without going into swap.
Call me lazy, but I think it is a bit pointless trying to predict the exact settings, since you will invariably miss something out of your calculation, or estimate elements badly. Far better to pick a general starting point then monitor-adjust-repeat until you get it right.
Size does figure in the equation though. In the same way you proportionately reduce % swap size as memory grows, you can also reduce the percentage of unallocated memory since 10% of 1TB is much bigger than 50% of 1G. :)
Cheers
Tim...
-- http://www.freelists.org/webpage/oracle-lReceived on Sun Apr 22 2012 - 02:59:42 CDT