Re: parallel instances

On Thu, 27 Jan 2005 21:20:15 GMT, "b c via OracleMonster.com" <forum_at_OracleMonster.com> wrote:

>1)On a Win2000 with Oracle 8.1.7.4 I have configured two parallel instances originally. Each instance has a service running on it. One service was configured for testing and a second to see wether there is any interference between parallel services. Both services/instances are started automatically at bootup.
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>The performance has been poor from the moment I started the services and changed it from manually to automatically (default: manually, stopped).
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>Is it true that parallel instances make an impact on the server performance even though the service is not started?
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>2) Oracle has the option to configure an typical database mainly for querying (datawarehouse option). How much difference does it performance-wise when choosing this datawarehosue option?

What, exactly, do you mean by "parallel instances" and then "parallel services"? I'm guessing your terminlogy is a bit loose, and you mean you have two seprarate but unrelated databases on the one server, each mounted by its own instance and running under its own Windows service. But I'm just guessing.

If the service (the windows service) is not running then you do not have an instance, you simply have a database: a collection of files on disk. Pretty tough for software that is not running to have any performance impact.

The choice of "configuring for querying (datawarehouse option)" merely sets some init.ora parms to favor high-volume query activity. I guess it might also pre-select a block size for db creation, I've never checked. Others will know. In any event, the parms don't even come into play until the instance is started up, and can always be changed to tune for the real world of your particular app.

Please clarify your terminology and provide some more precise detail. Describe your hardware platform. Clarify what you mean by "parallel" instances. There shouldn't be any "interference", but there well could be contention for resources -- cpu, memory, bandwidth to the disks ... but only if both are running at the same time! Peformance problems are due to specific bottlenecks which can be identified and addressed.
Thanks.

• Ed Stevens

Cohn's Law: The more time you spend in reporting on what you are doing, the less time you have to do anything. Stability is achieved when you spend all your time doing nothing but reporting on the nothing you are doing. Received on Thu Jan 27 2005 - 16:33:30 CST