Horton

Re: define pg_structiszero(addr, s, r)

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

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ranier Vilela <ranier.vf@gmail.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>, Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, Peter Eisentraut <peter@eisentraut.org>, pgsql-hackers@lists.postgresql.org
Date: 2024-10-28T15:08:31Z
Lists: pgsql-hackers 
Ranier Vilela <ranier.vf@gmail.com> writes:
> It seems to me that [reversing the loop direction] is more optimized.

That's far from clear: you're ignoring the possibility that memory
access logic is better optimized for forward scanning than reverse
scanning.  I'd stick with the forward scan without some extremely
detailed testing.

			regards, tom lane

Commits

  1. Use pg_memory_is_all_zeros() in PageIsVerifiedExtended()

  2. Optimize pg_memory_is_all_zeros() in memutils.h

  3. Remove use of pg_memory_is_all_zeros() in bufpage.c

  4. Add pg_memory_is_all_zeros() in memutils.h