"Mark Cave-Ayland" <m.cave-ayland@webbased.co.uk> writes:
> I'm still a little nervous about dropping down to CRC32 from CRC64 and so
> was just wondering what the net saving would be using one CRC64 across the
> whole WAL record?
None to speak of; the startup/teardown time is trivial. It's the
per-byte cost that hurts.
regards, tom lane