Re: Performance advice

> > configure it properly and trial & error. I do think the
> documentation could
> > be enhanced a bit here, but I'm sure there are some users who don't make
>
> Do you have any specific thoughts about documentation? Areas of
> confusion? Was it difficult to find the information in question, or was
> it simply unavailable?

I think the biggest area of confusion for me was that the various parameters
are very briefly described and no context is given for their parameters.
For example, from:
http://www.postgresql.org/docs/view.php?version=7.3&idoc=1&file=runtime-conf
ig.html

MAX_FSM_RELATIONS (integer)
Sets the maximum number of relations (tables) for which free space will be
tracked in the shared free-space map. The default is 100. This option can
only be set at server start.

There's not enough information there to properly tune postgres. A few
people suggested increasing this so I set mine to 4000. I don't have much
idea if that's too high, too low, just right. What would be nice if these
were put into context. Maybe come up with a matrix, with the settings and
various server configs. We could come up with the 5-10 most common server
configurations. So a user with 256k of ram and a single IDE disk will have
different range from a user with 2 gigs of ram and a SCSI RAID.

The next thing that really needs improving is the optimization section of
the FAQ (http://www.postgresql.org/docs/faqs/FAQ.html#3.6). This is a very
important section of the documentation and it's pretty empty. One thing
that was suggested to me is to move the WAL directory to another drive.
That could be in this FAQ section. effective_cache isn't mentioned either.
It'd be great to talk about server hardware as well, such as memory, whether
to put postgres on a dedicated server or keep it on the same server as the
apps/webapps.

Please don't misunderstand, the Postgres documentation is excellent. Some
improvements to the performance sections of the documentation would make a
huge difference.

Regards,
Michael