Re: wal_checksum = on (default) | off - Mailing list pgsql-patches

From Simon Riggs
Subject Re: wal_checksum = on (default) | off
Date
Msg-id 1167926200.20749.144.camel@silverbirch.site
Whole thread Raw
In response to Re: wal_checksum = on (default) | off  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: wal_checksum = on (default) | off  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: [HACKERS] wal_checksum = on (default) | off  (Florian Weimer <fweimer@bfk.de>)
List pgsql-patches
On Thu, 2007-01-04 at 10:00 -0500, Tom Lane wrote:
> "Simon Riggs" <simon@2ndquadrant.com> writes:
> > In this thread, I outlined an idea for reducing cost of WAL CRC checking
> > http://archives.postgresql.org/pgsql-hackers/2006-10/msg01299.php
> > wal_checksum = on (default) | off
>
> This still seems awfully dangerous to me.

Understood.

> > Recovery can occur with/without same setting of wal_checksum, to avoid
> > complications from crashes immediately after turning GUC on.
>
> Surely not.  Otherwise even the "on" setting is not really a defense.

Only when the CRC is exactly zero, which happens very very rarely.

--
  Simon Riggs
  EnterpriseDB   http://www.enterprisedb.com



pgsql-patches by date:

Previous
From: Tom Lane
Date:
Subject: Re: wal_checksum = on (default) | off
Next
From: Tom Lane
Date:
Subject: Re: wal_checksum = on (default) | off