Re: OSDL DBT-2 w/ PostgreSQL 7.3.4 and 7.4beta5

On Sun, Nov 02, 2003 at 07:25:38AM -0500, Rod Taylor wrote:
> On Sat, 2003-11-01 at 20:58, Mark Wong wrote:
> > I don't remember making a conscious decision between the number and integer
> > database type. Is that a significant oversight on my part?
>
> Numerics do exact math with support for arbitrary numbers. Unlike
> Oracle, PostgreSQL does not retype NUMBER to a faster type internally
> (like int).
>
> You may find a good sized improvement (possibly as much as 15%) by
> switching to integer as it will both reduce CPU load and storage
> requirements.

I've changed all the numerics to integers and reals, where it was appropriate
to maintain the precision specificed in the TPC-C spec. Here's a comparison
of results:

http://developer.osdl.org/markw/dbt2-pgsql/214/
- using all numerics
- metric 1831.78

http://developer.osdl.org/markw/dbt2-pgsql/217/
- integers and reals where appropriate
- metric 1972.94

Looks like I see about an 8% improvement in the metric with this instance. A
definite decrease in user time in the processor utilization chart, which I
presume is attributed to the 70% decrease in ticks to SearchCatCache in the
database as reported by oprofile. Can anyone explain that one?

Mark