Re: Page Checksums - Mailing list pgsql-hackers

From David Fetter
Subject Re: Page Checksums
Date
Msg-id 20111218184400.GB14268@fetter.org
Whole thread Raw
In response to Re: Page Checksums  (Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>)
Responses Re: Page Checksums
List pgsql-hackers
On Sun, Dec 18, 2011 at 12:19:32PM +0200, Heikki Linnakangas wrote:
> On 18.12.2011 10:54, David Fetter wrote:
> >On Sun, Dec 18, 2011 at 10:14:38AM +0200, Heikki Linnakangas wrote:
> >>On 17.12.2011 23:33, David Fetter wrote:
> >>>If this introduces new failure modes, please detail, and preferably
> >>>demonstrate, just what those new modes are.
> >>
> >>Hint bits, torn pages ->  failed CRC. See earlier discussion:
> >>
> >>http://archives.postgresql.org/pgsql-hackers/2009-11/msg01975.php
> >
> >The patch requires that full page writes be on in order to obviate
> >this problem by never reading a torn page.
> 
> Doesn't help. Hint bit updates are not WAL-logged.

What new failure modes are you envisioning for this case?  Any way to
simulate them, even if it's by injecting faults into the source code?

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com
iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics

Remember to vote!
Consider donating to Postgres: http://www.postgresql.org/about/donate


pgsql-hackers by date:

Previous
From: Dimitri Fontaine
Date:
Subject: Re: JSON for PG 9.2
Next
From: Tom Lane
Date:
Subject: Re: Command Triggers