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

Re: slow vacuum performance

From: pginfo <pginfo(at)t1(dot)unisoftbg(dot)com>
To: "scott(dot)marlowe" <scott(dot)marlowe(at)ihs(dot)com>
Cc: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: slow vacuum performance
Date: 2004-03-24 17:08:51
Message-ID: 4061C0A3.6C0E1C10@t1.unisoftbg.com (view raw or flat)
Thread:
Lists: pgsql-performance

scott.marlowe wrote:

> On Wed, 24 Mar 2004, pginfo wrote:
>
> > Hi,
> >
> > scott.marlowe wrote:
> >
> > > On Wed, 24 Mar 2004, 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.
> > >
> > > Is there a reason to not use just regular vacuum / analyze (i.e. NOT
> > > full)?
> > >
> >
> > Yes, in case I make massive updates (only in my case of cource)   for example
> > 2 M rows, I do not expect to have 2M new rows in next 180 days.That is the
> > reaso for running vacuum full.
> > My idea was to free unneedet space and so to have faster system.
> > It is possible that I am wrong.
>
> It's all about percentages.  If you've got an average of 5% dead tuples
> with regular vacuuming, then full vacuums won't gain you much, if
> anything.  If you've got 20 dead tuples for each live one, then a full
> vacuum is pretty much a necessity.  The generally accepted best
> performance comes with 5 to 50% or so dead tuples.  Keep in mind, having a
> few dead tuples is actually a good thing, as your database won't grow then
> srhink the file all the time, but keep it in a steady state size wise.

thanks for the good analyze,ivan.



In response to

pgsql-performance by date

Next:From: scott.marloweDate: 2004-03-24 18:13:55
Subject: Re: slow vacuum performance
Previous:From: Vivek KheraDate: 2004-03-24 17:05:49
Subject: Re: [ADMIN] Benchmarking postgres on Solaris/Linux

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group