Re: What ramifications are there for running two Instances on one host server.

"toddthom" <orclnwsgrp_at_hotmail.com> wrote in message news:94io0r$nru$1_at_nnrp1.deja.com...
> Hello Generous and All-Knowing,
>
> I'm a jdba and I'm currently involved in building an Operational Data
> Store and a Data Warehouse on one HPUX (11.0) N-Class server......two
> SID's one one node. We haven't actually built it yet, but, I thought
> Oracle's rule was a one to one relationship with regard to instance and
> database.....wouldn't this break the rule?

It would only break it if you assume that a database is the same thing as a node. The node is the HP Server -one physical box. The database is the collection of controlfiles+datafiles+redo logs that relate to your Data Warehouse, and the second database is the collection of controlfiles+datafiles+redo logs that relate to your Operational Datastore. Two databases, one node. Nothing wrong in that.

You will have to have two Instances managing those two databases -because the rule about 1 instance managing 1 database is always true (even in Parallel Server). Two Instances, one node. Nothing wrong with that, either.

Except... that performance on either Instance will be affected by the work being done on the other, and the i/o on one database will be affected by the i/o on the other.

So whilst there's nothing "wrong" with 2 or more databases and Instances on one node, it's not normally recommended for performance reasons.

>If not, what configuration
> recommendations would you make with regard to resources?
>

Extremely tricky to suggest anything without knowing the loads and work patterns for each database/instance. The simple (simplistic) advice is to go buy another HP Server.

Regards
HJR
> Thanks
>
> Todd
> Peace
>
>
>
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Received on Mon Jan 22 2001 - 20:28:24 CST