Re: Patch for fail-back without fresh backup - Mailing list pgsql-hackers

On 14.06.2013 16:21, Tom Lane wrote:
> Heikki Linnakangas<hlinnakangas@vmware.com>  writes:
>> On 14.06.2013 16:08, Tom Lane wrote:
>>> Refresh my memory as to why we need to WAL-log hints for checksumming?
>
>> Torn pages:
>
> So it's not that we actually need to log the individual hint bit
> changes, it's that we need to WAL-log a full page image on the first
> update after a checkpoint, so as to recover from torn-page cases.
> Which one are we doing?

Correct. We're doing the latter, see XLogSaveBufferForHint().

- Heikki