Re: New to PostgreSQL, performance considerations

At 11:11 AM 12/13/2006, Cosimo Streppone wrote:

>Interesting, eh?
>
>Cosimo

What I find interesting is that so far Guido's C2D Mac laptop has
gotten the highest values by far in this set of experiments, and no
one else is even close.
The slowest results, Michael's, are on the system with what appears
to be the slowest CPU of the bunch; and the ranking of the rest of
the results seem to similarly depend on relative CPU
performance. This is not what one would naively expect when benching
a IO intensive app like a DBMS.

Given that the typical laptop usually has 1 HD, and a relatively
modest one at that (the fastest available are SATA 7200rpm or
Seagate's perpendicular recording 5400rpm) in terms of performance,
this feels very much like other factors are bottlenecking the
experiments to the point where Daniel's results regarding compiler
options are not actually being tested.

Anyone got a 2.33 GHz C2D box with a decent HD IO subsystem more
representative of a typical DB server hooked up to it?

Again, the best way to confirm/deny Daniel's results is to duplicate
the environment he obtained those results with as closely as possible
(preferably exactly) and then have someone else try to duplicate his results.

Also, I think the warnings regarding proper configuration of pgbench
and which version of pgbench to use are worthy of note. Do we have
guidance yet as to what checkpoint_segments should be set
to? Should we be considering using something other than pgbench for
such experiments?

Ron Peacetree