On Tue, Dec 27, 2011 at 8:05 PM, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:
> On 25.12.2011 15:01, Kevin Grittner wrote:
>>
>> I don't believe that. Double-writing is a technique to avoid torn
>> pages, but it requires a checksum to work. This chicken-and-egg
>> problem requires the checksum to be implemented first.
>
>
> I don't think double-writes require checksums on the data pages themselves,
> just on the copies in the double-write buffers. In the double-write buffer,
> you'll need some extra information per-page anyway, like a relfilenode and
> block number that indicates which page it is in the buffer.
How would you know when to look in the double write buffer?
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