Re: Page Checksums

Stephen Frost <sfrost@snowman.net>

From: Stephen Frost <sfrost@snowman.net>
To: Aidan Van Dyk <aidan@highrise.ca>
Cc: Josh Berkus <josh@agliodbs.com>, pgsql-hackers@postgresql.org
Date: 2011-12-19T14:18:21Z
Lists: pgsql-hackers
* Aidan Van Dyk (aidan@highrise.ca) wrote:
> #) Anybody investigated putting the CRC in a relation fork, but not
> right in the data block?  If the CRC contains a timestamp, and is WAL
> logged before the write, at least on reading a block with a wrong
> checksum, if a warning is emitted, the timestamp could be looked at by
> whoever is reading the warning and know tht the block was written
> shortly before the crash $X $PERIODS ago....

I do like the idea of putting the CRC info in a relation fork, if it can
be made to work decently, as we might be able to then support it on a
per-relation basis, and maybe even avoid the on-disk format change..

Of course, I'm sure there's all kinds of problems with that approach,
but it might be worth some thinking about.

	Thanks,

		Stephen