Horton

Re: Performance Improvement by reducing WAL for Update Operation

Peter Geoghegan <pg@heroku.com>

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From: Peter Geoghegan <pg@heroku.com>
To: Heikki Linnakangas <hlinnakangas@vmware.com>
Cc: Andres Freund <andres@2ndquadrant.com>, Fujii Masao <masao.fujii@gmail.com>, Bruce Momjian <bruce@momjian.us>, Robert Haas <robertmhaas@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Mike Blackwell <mike.blackwell@rrd.com>
Date: 2014-02-05T18:57:57Z
Lists: pgsql-hackers 
On Wed, Feb 5, 2014 at 12:50 AM, Heikki Linnakangas
<hlinnakangas@vmware.com> wrote:
>> I think there's zero overlap. They're completely complimentary features.
>> It's not like normal WAL records have an irrelevant volume.
>
>
> Correct. Compressing a full-page image happens on the first update after a
> checkpoint, and the diff between old and new tuple is not used in that case.

Uh, I really just meant that one thing that might overlap is
considerations around the choice of compression algorithm. I think
that there was some useful discussion of that on the other thread as
well.


-- 
Peter Geoghegan

Commits

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