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

Re: Vacuum looping?

From: Decibel! <decibel(at)decibel(dot)org>
To: Steven Flatt <steven(dot)flatt(at)gmail(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Vacuum looping?
Date: 2007-07-31 01:46:37
Message-ID: D494F6AB-F9C7-4A61-B050-181BEE320312@decibel.org (view raw or flat)
Thread:
Lists: pgsql-performance
On Jul 30, 2007, at 9:04 AM, Steven Flatt wrote:
> On 7/28/07, Jim C. Nasby <decibel(at)decibel(dot)org> wrote: What are your  
> vacuum_cost_* settings? If you set those too aggressively
> you'll be in big trouble.
>
> autovacuum_vacuum_cost_delay = 100

Wow, that's *really* high. I don't think I've ever set it higher than  
25. I'd cut it way back.

> autovacuum_vacuum_cost_limit = 200
>
> These are generally fine, autovacuum keeps up, and there is minimal  
> impact on the system.
>
> vacuum_cost_delay = 100
> vacuum_cost_limit = 1000
>
> We set this cost_limit a little higher so that, in the few cases  
> where we have to intervene manually, vacuum runs faster.

IIRC, when the cost delay was initially introduced (8.0), someone did  
testing and decided that the cost limit of 200 was optimal, so I  
wouldn't go changing it like that without good reason.

Normally, I'll use a delay of 10ms on good disk hardware, and 20ms on  
slower hardware.
-- 
Decibel!, aka Jim Nasby                        decibel(at)decibel(dot)org
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)



In response to

pgsql-performance by date

Next:From: Tom LaneDate: 2007-07-31 05:19:16
Subject: Re: disk filling up
Previous:From: Karl DenningerDate: 2007-07-31 01:08:44
Subject: Query optimization....

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