Date: Tue, 7 Jan 2020 18:17:17 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, craig@2ndquadrant.com,
	pgsql-hackers@postgresql.org
Subject: Re: xact_start for walsender & logical decoding not updated
Message-ID: <20200107211717.GA20056@alvherre.pgsql>
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On 2019-Dec-29, Tomas Vondra wrote:

> On Fri, Dec 27, 2019 at 04:46:18PM -0300, Alvaro Herrera wrote:
> > 
> > This patch changes xact.c to avoid updating transaction start timestamps
> > for walsenders (maybe more commentary is desirable).  I think logical
> > decoding is just a special form of walsender and thus it would also be
> > updated by this patch, unless I misunderstood what Tomas explained.
> > 
> 
> It's true walsender should not be doing any read-write transactions or
> executing statements (well, maybe a decoding plugin could, but using
> historic snapshot).
> 
> So I agree not leaving xact_start for walsender processes seems OK.

OK, I pushed my patch to branches 10 - master.
(See https://postgr.es/m/20200107211624.GA18974@alvherre.pgsql )

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