Proposal for Re-ordering CONF (was: Re: GUC and postgresql.conf docs)

Bruce,

> I have developed the following patch to address these issues. I have
> removed the lock GUC settings from postgresql.conf, as suggested. (They
> aren't even enabled in the general builds.)

Great! Just to keep you from getting complacent, what follows is a proposal
for re-ordering the settings in the postgresql.conf.sample file. (sorry for
replying to your thread on a different list; I'm not subscribed to PATCHES).

THE PROPOSAL: We should re-order the settings in postgresql.conf.sample in
order to make more logical groupings per the attached outline. The online
documenation should be then re-sorted to match this order.

THE REASONS WHY: Our current ordering of settings in the CONF file is largely
based on history (i.e. based on when settings were added rather than any more
logical order). This makes understanding the CONF file baffling to
newcomers, and even experienced DBAs can miss important settings because they
are not grouped with their logical associates.
For that matter, the current ordering can be baffling to developers. When I
started this thread, Tom wasn't sure that CONF and GUC.c corresponded 100%.
And no wonder! postgresql.conf.sample is in one order, the "Run-time
configuration" doc page in a second order, and GUC.c in yet a third order!
It took me most of an afternoon just to match up the various options. The
CONF file and the docs should be in the same order, leaving us only two
orderings to keep track of.

THE ARGUMENT AGAINST: This would be an annoyance for anyone who "diffs" their
conf files as part of upgrading. I cannot think of any other objection,
except for the work involved, which I am quite willing to help with.

THE OUTLINE ATTACHED: is my proposed ordering. I've put it in outline form,
so that the groupings I'm using are obvious; I feel that the final
postgresql.conf.sample should keep the group and subgroup headers as comments
for additional clarity. I welcome improvements and suggestions -- the only
thing I'm attached to is the idea of logical re-ordering, not this particular
order.
PLEASE NOTE THAT THIS OUTLINE IS BASED ON 7.3.2 postgresql.conf. My laptop
is in the shop and I don't have a copy of 7.4 cvs on my back-up computer.
If my proposal is accepted in general, I will flesh it out for 7.4 before
June 15.

COMMITTMENT TO FOLLOW-UP: I will also be posting an article entitled "The
Annotated PostgreSQL.conf" either on Techdocs or at Elein's web site based on
this ordering to help people decipher their .conf files. This will include
the official docs, comments from the -PERFORMANCE mailing list, the command
line options, and whether or not each variable can be SET by the user.

--
Josh Berkus
Aglio Database Solutions
San Francisco