Re: Reasonable performance ?

frank.van.bortel_at_gmail.com wrote:
> Adrian Simpson schreef:
>
> > We're not entirely sure that we have got a system that is performing
> > well.
> >
> > We had a partitioned table with 2254 partitions, of which 260 had data
> > in, varying between 1 and ~41,000 rows.
>
> > The DB is set up to parallelise using 16 processors, but at any one
> > time, only 8 processes (ora_pxxx_<dbname>) seem to be active.
> >
>
> 41k Rows is not much - I would say the overhead for the parallel query
> is more than the time it would take to retrieve these.
> Although I am not absolutely certain your queries run prallel 8,
> I would suggest to take a closer look at your break even point.
> Relatively few records are processed faster without parallel query.
> What actually is "few" is entirely for you to find out.
> My experience is the tbreak even point is
> at about 200,000 rows. Different hardware, different setup, so
> not comparable at all!

Good point. Received on Fri Sep 15 2006 - 08:45:14 CDT