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

Re: Re: dramatic slowdown. . .fixed by vacuum

From: The Hermit Hacker <scrappy(at)hub(dot)org>
To: Joe Slag <jslag(at)visi(dot)com>
Cc: pgsql-novice(at)postgresql(dot)org
Subject: Re: Re: dramatic slowdown. . .fixed by vacuum
Date: 2000-07-21 20:20:23
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-novice
On Fri, 21 Jul 2000, Joe Slag wrote:

> On Fri, Jul 21, 2000 at 12:36:35PM -0700, WOLF, PATRICK wrote:
> > Try running vacuum on the table or the database.  Here's an excerpt from the
> > man on vacuum:
> > 
> [snip]
> > 
> > 
> Thanks to all who responded.  I vacuumed out foo, and sure enough 
> the select time is down to 10 seconds again.
> I see in the docs the suggestion: 
>     We recommend that active production databases be VACUUMM-ed nightly
> Is this how people tend to do their vacuuming?  Does anyone do programmatic
> vacuums instead of / in addition to a nightly run?  Is vacuuming mainly
> necessary after big deletes, or are there other common situations 
> requiring it?

UPDATEs are a combination of 'INSERT new tuple/mark old as DELETEd', so
for each UPDATE, you are adding one more tuple to the table but not
removing anything.  VACUUM removes that DELETEd tuple.  

In response to

pgsql-novice by date

Next:From: Andrew McMillanDate: 2000-07-21 21:35:47
Subject: Re: Re: dramatic slowdown. . .fixed by vacuum
Previous:From: Anthony E . GreeneDate: 2000-07-21 20:20:22
Subject: Re: Re: dramatic slowdown. . .fixed by vacuum

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