"Zeugswetter Andreas ADI SD" <ZeugswetterA@spardat.at> writes:
> Ok, so when you need CRC's on a replicate (but not on the master) you
> turn it
> off during standby replay, but turn it on when you start the replicate
> for normal operation.
Thought: even when it's off, the CRC had better be computed for
shutdown-checkpoint records. Else there's no way to turn it on even
with a postmaster restart --- unless we accept the idea of poking a hole
in the normal mode. (Which I still dislike, and even more so if the
special value is zero. Almost any other value would be safer than zero.)
On the whole, though, I still don't want to put this in. I don't think
Simon has thought it through sufficiently, and we haven't even seen any
demonstration of a big speedup.
(Another hole in the implementation as given: pg_resetxlog.)
regards, tom lane