We have the setup of 1 oracle database on 1 linux server. This way we only plan 
to use the memory just what Oracle needs (and some for Linux and monitoring 
stuff). We have always 2 vdisks for swap and then 1 mdisk as swap.
For your case I think you can have memory at the Oracle requirement (SGA+PGA) 
and give a swap on vdisk for some amount.

Also depends on version, if you have Oracle 12 or above and use Multitenant 
then SGA+PGA is more shared among the databases. Normally by using multitenant 
memory can be less than if used standalone. Multitenant is free till 3 
pluggable databases, so If you have more, more instances are still needed (or 
pay for it).

Met vriendelijke groet,
Herald ten Dam
Database Specialist Oracle, Medior z/VM

ICU IT Services BV
Transistorstraat 55b  I  1322 CK  ALMERE

M 06 – 28 891 653  I  E 
[email protected]<mailto:[email protected]>
T 088 – 5 234 123  I  
www.icu-it.nl<https://mail.tonec.nl/owa/redir.aspx?C=VXsWzolNszaPfEV0NyI4hHlHi_HLsvmJPdc-hUPEoam3bq_3CljVCA..&URL=http%3a%2f%2fwww.icu-it.nl%2f>
  I  KvK 32135776

________________________________
Van: Linux on 390 Port <[email protected]> namens Rob van der Heij 
<[email protected]>
Verzonden: woensdag 17 juni 2020 13:29
Aan: [email protected] <[email protected]>
Onderwerp: Re: Running multiple Oracle on a single Linux guest

On Wed, 17 Jun 2020 at 09:14, Peter <[email protected]> wrote:

> So I can't cap memory based on a oracle instance ? Like prioritising each
> oracle instance ?
>

You can to some extent. You define the maximum by SGA and PGA per instance,
and things like connection pools. The actual usage varies somewhat by
workload. But very few customers will make their guests large enough to
hold all database instances at their maximum usage. That would leave a lot
of excess memory that Linux will use for other things (like cache data).
Instead, they share much of the white space and cross their fingers.

If your databases have short burst of activity and long periods of idle, it
might be more attractive to configure Linux guests to fit that instance and
let z/VM take resources away when there is demand from others and the
instance is idle.

Rob

----------------------------------------------------------------------
For LINUX-390 subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO LINUX-390 or visit
http://www2.marist.edu/htbin/wlvindex?LINUX-390

----------------------------------------------------------------------
For LINUX-390 subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO LINUX-390 or visit
http://www2.marist.edu/htbin/wlvindex?LINUX-390

Reply via email to