> > It wouldn't help you recover, but you would be able to report that
> > you cannot recover.
>
> How? The scenario Vadim is pointing out is where the disk
> drive writes a changed data block in advance of the WAL log entry
> describing the change. Then power drops and the WAL entry never gets
> made. At restart, how will you realize that that data block now
> contains data you don't want? There's not even a log entry telling
> you you need to look at it, much less one that tells you what should
> be in it.
>
> AFAICS, disk-block CRCs do not guard against mishaps involving intended
> writes. They will help guard against data corruption that might creep
> in due to outside factors, however.
I couldn't describe better -:)
Vadim