Re: Performance problem

Shankar wrote:

> hello,
> We are moving one of the user from one database ( database A) to
> another database (database B)
>
> Both are cost based and query executed against the db A comes back in
> 10 seconds (its a big query), but it takes about 2 minutes+ in the db
> B.
>
> Server configuration are same ( db A's server and db B's server) and
> all the parameter set up for db A and db B are exactly same.
>
> Currently user count on each server is also very minimum.
> Explain plan for the query is same for both the dbs.
>
> so what are we missing? why so much difference in the performance?

You say it CBO - how are your statistics?

I'm not even sure you have the same operating system (and patch level) under A and B.

I assume you have the same DB version (and patch level), but that's an assumption.

I also assume that subtle things like disk subsystem and (if relevant) async-io, etc. are set up the same as well.

And, since you are concerned about this, I assume you have identical data in both systems (not similar, not a 'representative subset' - identical) from which to base your concern.

Any other load on the 'slower' machine? Any difference in disk environment? Any chance that the disk, disk controller, or memory on the 'slower' machine is unhealthy?

FInally, what other investigations have you done (such as StatsPack)? Received on Tue Jul 20 2004 - 22:37:07 CDT