Re: New to PostgreSQL, performance considerations

Tom Lane wrote:
> "Joshua D. Drake" <jd@commandprompt.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?

What is to stop us from running the new pgbench against older versions
of PGSQL?  Any stats taken from a run of pgbench a long time ago
probably aren't relevant against a modern test anyway as the underlying
hardware and OS are likely to have changed or been updated.