Skip site navigation (1) Skip section navigation (2)

Re: slow vacuum performance

From: pginfo <pginfo(at)t1(dot)unisoftbg(dot)com>
To: Bill Moran <wmoran(at)potentialtech(dot)com>
Cc: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: slow vacuum performance
Date: 2004-03-24 14:21:32
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
Hi Bill,
I am vacuuming every 24 h.
I have a cron script about i.
But if I make massive update (for example it affects 1 M rows) and I start vacuum,
it take this 2 h.
Also I will note, that this massive update is running in one transaction ( I can
not update 100K and start vacuum after it).


Bill Moran wrote:

> pginfo wrote:
> > Hi,
> >
> > I am running pg 7.4.1 on linux box.
> > I have a midle size DB with many updates and after it I try to run
> > vacuum full analyze.
> > It takes about 2 h.
> > If I try to dump and reload the DB it take 20 min.
> >
> > How can I improve the vacuum full analyze time?
> How often are you vacuuming?  If you've gone a LONG time since the last vacuum,
> it can take quite a while, to the point where a dump/restore is faster.
> A recent realization that I've had some misconceptions about vacuuming led me
> to re-read section 8.2 of the admin guide (on vacuuming) ... I highly suggest
> a review of these 3 pages of the admin manual, as it contains an excellent
> description of why databases need vacuumed, that one can use to determine how
> often vacuuming is necessary.
> --
> Bill Moran
> Potential Technologies

In response to

pgsql-performance by date

Next:From: scott.marloweDate: 2004-03-24 16:26:40
Subject: Re: slow vacuum performance
Previous:From: Bill MoranDate: 2004-03-24 14:07:27
Subject: Re: slow vacuum performance

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group