Re: Cost of XLogInsert CRC calculations - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Cost of XLogInsert CRC calculations
Date
Msg-id 17441.1116393146@sss.pgh.pa.us
Whole thread Raw
In response to Re: Cost of XLogInsert CRC calculations  (Greg Stark <gsstark@mit.edu>)
Responses Re: Cost of XLogInsert CRC calculations  (Bruce Momjian <pgman@candle.pha.pa.us>)
Re: Cost of XLogInsert CRC calculations  ("Mark Cave-Ayland" <m.cave-ayland@webbased.co.uk>)
Re: Cost of XLogInsert CRC calculations  (Manfred Koizar <mkoi-pg@aon.at>)
List pgsql-hackers
Greg Stark <gsstark@mit.edu> writes:
> Tom Lane <tgl@sss.pgh.pa.us> writes:
>> Do we know that?  The results I showed put at least one fundamentally
>> 32bit platform (the PowerBook I'm typing this on) at dead par for 32bit
>> and 64bit CRCs.  

> Wait, par for 32-bit CRCs? Or for 64-bit CRCs calculated using 32-bit ints?

Right, the latter.  We haven't actually tried to measure the cost of
plain 32bit CRCs... although I seem to recall that when we originally
decided to use 64bit, someone put up some benchmarks purporting to
show that there wasn't much difference.
        regards, tom lane


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