Re: [Again] Postgres performance problem

On Wed, 12 Sep 2007, Scott Marlowe wrote:

> I'm getting more and more motivated to rewrite the vacuum docs. I think
> a rewrite from the ground up might be best... I keep seeing people
> doing vacuum full on this list and I'm thinking it's as much because of
> the way the docs represent vacuum full as anything.

I agree you shouldn't start thinking in terms of how to fix the existing
documentation. I'd suggest instead writing a tutorial leading someone
through what they need to know about their tables first and then going
into how vacuum works based on that data.

As an example, people throw around terms like "index bloat" and "dead
tuples" when talking about vacuuming. The tutorial I'd like to see
somebody write would start by explaining those terms and showing how to
measure them--preferably with a good and bad example to contrast. The way
these terms are thrown around right now, I don't expect newcomers to
understand either the documentation or the advice people are giving them;
I think it's shooting over their heads and what's needed are some
walkthroughs. Another example I'd like to see thrown in there is what it
looks like when you don't have enough FSM slots.

--
* Greg Smith gsmith(at)gregsmith(dot)com http://www.gregsmith.com Baltimore, MD