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From: Chapman Flack <chap@anastigmatix.net>
To: Michael Paquier <michael.paquier@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: AdvanceXLInsertBuffer vs. WAL segment compressibility
Date: Tue, 26 Jul 2016 20:20:32 -0400
Message-ID: <5797FE50.7070600@anastigmatix.net> (raw)
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On 07/26/16 20:01, Michael Paquier wrote:
> On Tue, Jul 26, 2016 at 9:48 PM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> Does any body else see the use case
>> reported by Chapman important enough that we try to have some solution
>> for it in-core?
> 
> The lack of updates in the pg_lesslog project is a sign that it is not
> that much used. I does not seem a good idea to bring in-core a tool
> not used that much by users.

Effectively, it already was brought in-core in commit 9a20a9b.
Only, that change had an unintended consequence that *limits*
compressibility - and it would not have that consequence, if
it were changed to simply set xlp_pageaddr to InvalidXLogRecPtr
in the dummy zero pages written to fill out a segment.

-Chap


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