Horton

Re: Cost of XLogInsert CRC calculations

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Mark Cave-Ayland" <m.cave-ayland@webbased.co.uk>
Cc: "'Greg Stark'" <gsstark@mit.edu>, "'Manfred Koizar'" <mkoi-pg@aon.at>, "'Bruce Momjian'" <pgman@candle.pha.pa.us>, pgsql-hackers@postgresql.org
Date: 2005-06-01T14:07:36Z
Lists: pgsql-hackers 
"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