Re: Parallelserver: What to think about?

In article <916822725.99419_at_services>,
  "Timo Feickert" <timo_at_prompt.de.NOWHERE.COM> wrote:
> hello world,
>
> we are developing a standard client/server app, accessing oracle (7 or
> ms-sql) via odbc (over sql-net).
>
> one of our customers is thinking about purchasing oracle "parallel-server
> (enterprise edition)" and asks whether this is supported. are there any
> "specialities" we should take into account from the client point of view or
> is the type of server edition totally transparent to the client - as it
> should be?
>
> any hints appreciated - tyia
>
> .Timo
>

There have been several posts on parallel servers, OPS, recently. You may want to try the archives.

OPS is probably not going to be invisible to the client depending on how your application works and how you configure sqlnet on the client. If the client has sqlnet configured on it and it points to instance A, which then crashes, an attempt by the client to re-logon to the same instance will then fail. An attemp to login to instance B should however work. There is supposed to be a way to assign two ip addresses to an instance via sqlnet, but it never worked for us. It has been a couple of releases since we tried to do this.

If the application requires the use of server based OS files you generally have a single point of failure.

The use of OPS depends largely on why you want OPS. OPS can be used to allow smaller machines to handle a big application or to provide hardware backup and quick recovery from most failures. i.e., standby type mode. OPS works easiest with applications that can be partitioned, that is, certain tables are updated from specific screens used by specific users and these users are assigned to instance A while another group of users and their screens are assigned to instance B. The tables from group A are in one set of tablespaces and the tables for group B are in another. This reduces contention on the same Oracle data blocks between the instances.

The Oracle Parallel Server Concepts manual is pretty good and explains where OPS works best and where problems exist. We have had good luck with it.

Mark D. Powell

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Wed Jan 20 1999 - 08:55:12 CST