Re: Would you recommend having multiple instances on the same box?

Daniel Morgan wrote:

> > <snipped
> >
> >
> > [second rant] probably much more important is ensuring that the application code
> > does not reside on the same box as the database. As far as I'm concerned, the
> > failure to do this is one of the bigger reasons why Oracle is considered
> > expensive - end up needing to get multiple CPU licenses to handle a 1-CPU load.
>
> Are you recommending application code in the front-end or middle-tier ... no PL/SQL
> ... or are you recommending use of database links?

I recommend that the application be properly partitioned based on a balance of network traffic, CPU load, etc. I'm also totally in favor of 3-tier (or n-tier) computing, having had the experience of supporting client-server for multitudes of clients (try rolling out SQL*Net to 2200 machines overnight!)

The database tier could have application logic if applicable. However, I am generally against running most batch-style programs (PERL, C, C++, etc.) on the DB box. I am also generally against putting the screen management code, such as JSPs, on the DB box.

Basically what I'm for is including the cost of the multiple boxes, the cost of the licenses, the cost of development effort and the cost of maintenance effort in the calculation to decide what goes where. In some cases DB-links may be the right answer.

> Simply put one gets the most database for their licensing dollars with one
> database-instance on one machine with multiple schemas rather than multiple
> databases-instances on a single machine. At least when licensing by CPU. And the use
> of machine resources is less with a smaller number of processes and only a single
> SGA.
>

Yes - one instance supporting multiple applications gives the greatest bang for the buck. Unfortunately few DBAs, fewer managers, and even fewer 3rd party app vendors know how to handle that scenario. And of course, there are 1,000s of arguments which it shouldn't be done.

/Hans Received on Sat Apr 19 2003 - 20:12:08 CDT