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

Re: Heavy write activity on first vacuum of fresh TOASTdata

From: Simon Riggs <simon(at)2ndquadrant(dot)com>
To: Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Heavy write activity on first vacuum of fresh TOASTdata
Date: 2007-12-13 21:40:10
Message-ID: 1197582010.4255.1912.camel@ebony.site (view raw or flat)
Thread:
Lists: pgsql-performance
On Thu, 2007-12-13 at 15:19 -0600, Kevin Grittner wrote:
> >>> On Thu, Dec 13, 2007 at 12:12 PM, in message
> <1197569564(dot)4255(dot)1855(dot)camel(at)ebony(dot)site>, Simon Riggs <simon(at)2ndquadrant(dot)com>
> wrote: 
> > On Thu, 2007-12-13 at 11:46 -0600, Kevin Grittner wrote:
> >> If the hint bit changes are written to the WAL ...
> > 
> > They're not.
>  
> So one would expect a write-intensive initial vacuum after a
> PITR-style recovery?

Very perceptive. I was just thinking about that myself. An interesting
issue when running with full_page_writes off.
 
> What impact would lack of the hint bits have until a vacuum?

Vacuum isn't important here. Its the first idiot to read the data that
gets hit.

-- 
  Simon Riggs
  2ndQuadrant  http://www.2ndQuadrant.com


In response to

Responses

pgsql-performance by date

Next:From: Kevin GrittnerDate: 2007-12-13 23:43:27
Subject: Re: Heavy write activity on first vacuum of freshTOAST data
Previous:From: Kevin GrittnerDate: 2007-12-13 21:19:34
Subject: Re: Heavy write activity on first vacuum of freshTOAST data

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