Re: Vacuum goes worse

[Alvaro Herrera <alvherre(at)commandprompt(dot)com>]

Stefano Dal Pra escribió:
> Your first post says vacuum goes worse (slower).
> I see that you do not issue the -f option (FULL VACUUM).
> 
> I had a similar situation with a server (with frequent update)
> performing nightly vacuumdb. After a few many days it went
> slower and slower.

When you have that problem, the solution is to issue more plain vacuum
(not full) more frequently.  If it's a highly updated table, then maybe
once per hour or more.  It depends on the update rate.

> With psql 8.2.x we adopted pg_autovacuum which seems to perform good,
> even thought
> i do not clearly understand whether it occasionally performs a full
> vacuum (i think he does'nt).

It doesn't because it's normally not necessary.  Also, we don't want to
be acquiring exclusive locks in a background automatic process, so if
you really need vacuum full (and I question your need to) then you must
issue it yourself.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.