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

Re: WAL file utilization question

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: kadams(at)mxlogic(dot)com
Cc: "Jim C(dot) Nasby" <decibel(at)decibel(dot)org>, pgsql-admin(at)postgresql(dot)org
Subject: Re: WAL file utilization question
Date: 2007-05-16 20:02:57
Message-ID: 6775.1179345777@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-admin
Keaton Adams <kadams(at)mxlogic(dot)com> writes:
> Well, no, I'm not that paranoid where I expect checkpoints to be taking
> place so often.  I do find it interesting that controlling checkpoint
> frequency is a factor of the number of WAL files available.  In order to
> get up to 60 second checkpoints I had to set checkpoint_segments to 25,
> which resulted in the creation of 52 log files in data/pg_xlog.  So for
> 120 second checkpoints I will need to have up to 104 log files in
> data/pg_xlog available?

No, it's nonlinear, precisely because of the
checkpoints-increase-the-log-size effect.  Given the size of modern
disks, I don't see why a couple Gb of WAL space is a problem anyhow
for a large database.

			regards, tom lane

In response to

pgsql-admin by date

Next:From: Peter EisentrautDate: 2007-05-17 07:33:40
Subject: Re: pg_dump not enough space to create a backup FreeBSD 6.1?
Previous:From: Tom LaneDate: 2007-05-16 19:41:03
Subject: Re: pg_dump not enough space to create a backup FreeBSD 6.1?

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