Re: Overhauling GUCS

* Andreas Pflug <pgadmin(at)pse-consulting(dot)de> [080606 04:50]:
> David E. Wheeler wrote:
> >
> >How about a simple rule, such as that machine-generated comments start
> >with "##", while user comments start with just "#"? I think that I've
> >seen such a rule used before. At any rate, I think that, unless you
> >have some sort of line marker for machine-generated comments, there
> >will be no way to tell them apart from user comments.
>
> Two heretical questions:
> Do we need user generated comments at all?
> I can't remember ever having used any comment in postgresql.conf.

Well, I have, mainly to leave traces as to what and why I've changed
something from a default/previous value, based on "chagne, hope, and
test" style tuning.

And the one that Greg brought up earlier:
## Don't make this too high, or linux OOM will kill ther server!!!

I'm guessing that comment was put in for a reason too.

> Why do so many people here insist on editing postgresql.conf as primary
> means of changing config params?
> Isn't a psql -c "SET foo=bar; MAKE PERSISTENT" just as good as sed'ing
> postgresql.conf or doing it manually?

I would guess main for 3 reasons:

1) It's always been that way, it's the traditional "unix" way, and many
admins are comfortable being able to comment/make quick test
changes with simple text files.
2) Their postgresql.conf are distrubuted/synced/generated from central
provisioning/SCM system
3) PostgreSQL the server isn't even running

> Looking around for different approaches, network appliances come to my
> mind, e.g. Cisco routers and PIX. You have 3 ways to configure a pix:
> - use a command line (using ssh or telnet, eqivalent to psql); WRITE
> MEMORY to make the changes survive a reboot.
> - use a web interface (or similar tool)
> - use tftp to up/download the complete config in and out, editing the
> file. User comments will be lost, with the exception of those that have
> been applied with special comment commands (equivalent to "comment on").

And, of course, other server software comes to mind too:
apache, bind, postfix, sendmail, dhcpd, sshd, cron, xinetd... ;-)

a.
--
Aidan Van Dyk Create like a god,
aidan(at)highrise(dot)ca command like a king,
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