Re: New to PostgreSQL, performance considerations

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

"Joshua D. Drake" <jd(at)commandprompt(dot)com> writes:
> On Wed, 2006-12-13 at 18:36 -0800, Josh Berkus wrote:
>> Mostly, though, pgbench just gives the I/O system a workout.  It's not a 
>> really good general workload.

> It also will not utilize all cpus on a many cpu machine. We recently
> found that the only way to *really* test with pgbench was to actually
> run 4+ copies of pgbench at the same time.

The pgbench app itself becomes the bottleneck at high transaction
rates.  Awhile back I rewrote it to improve its ability to issue
commands concurrently, but then desisted from submitting the
changes --- if we change the app like that, future numbers would
be incomparable to past ones, which sort of defeats the purpose of a
benchmark no?

			regards, tom lane