From: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Subject: Re: [HACKERS] WAL logging problem in 9.4.3?
To: Michael Paquier <michael@paquier.xyz>,
 Heikki Linnakangas <hlinnaka@iki.fi>
Cc: Robert Haas <robertmhaas@gmail.com>,
 "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
References: <20180105041040.GI2416@tamriel.snowman.net>
 <20180111.170355.123986255.horiguchi.kyotaro@lab.ntt.co.jp>
 <20180330.100646.86008470.horiguchi.kyotaro@lab.ntt.co.jp>
 <20180704045912.GG1672@paquier.xyz>
 <df32e286-ae2b-f45a-8f2e-4fa02684300b@iki.fi>
 <20180711033241.GQ1661@paquier.xyz>
 <aac8e19b-9159-e473-77be-53f80b658190@2ndQuadrant.com>
 <08b11907-d0b2-c396-2978-ba5aac1972df@iki.fi>
 <CA+TgmoZGn7MmMGRu4NkfxyXKSCzmvq1JvqsWm=hN=GJDMTfTKg@mail.gmail.com>
 <026AD6A1-3396-47F4-B87E-77E3F139D166@iki.fi>
 <20180717000129.GA3388@paquier.xyz>
Message-ID: <3c1cf991-8846-9a6f-c669-e21f8ea9a6a4@2ndQuadrant.com>
Date: Tue, 17 Jul 2018 08:28:47 -0400
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On 07/16/2018 08:01 PM, Michael Paquier wrote:
>
>
> I doubt as well that we'd be able to catch all the holes as well as the
> conditions where the optimization could be run safely are rather
> basically impossible to catch beforehand.  I'd like to vote for getting
> rid of this optimization for COPY, this can hurt more than it is
> helpful.  Per the lack of complaints, this could happen only in HEAD?


Well, we'd be getting rid of it because of a danger of data loss which 
we can't otherwise mitigate. Maybe it does need to be backpatched, even 
if we haven't had complaints.

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services