From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marko Tiikkaja <marko@joh.to>
cc: Michael Paquier <michael.paquier@gmail.com>,
        PostgreSQL mailing lists <pgsql-bugs@postgresql.org>
Subject: Re: BUG #14830: Missed NOTIFications, PostgreSQL 9.1.24
In-reply-to: 
 <CAL9smLAQOMNzREjJy-M8kpqGOGYdub3wD1uPb38xeHHRN=TTZA@mail.gmail.com>
References: <20170926182935.14128.65278@wrigleys.postgresql.org>
 <CAB7nPqRYq+SRKxW+Pbf6bs=6QJZYHC+93ax4+Oj5Xdz5QNyq8w@mail.gmail.com>
 <CAL9smLAPgt9vy_dstsdz-LBpa0PgKs8aiucVkMUV0u=SM6=fJA@mail.gmail.com>
 <CAL9smLAQOMNzREjJy-M8kpqGOGYdub3wD1uPb38xeHHRN=TTZA@mail.gmail.com>
Comments: In-reply-to Marko Tiikkaja <marko@joh.to>
	message dated "Tue, 10 Oct 2017 14:39:49 +0200"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <15644.1507643938.1@sss.pgh.pa.us>
Date: Tue, 10 Oct 2017 09:58:58 -0400
Message-ID: <15645.1507643938@sss.pgh.pa.us>
Precedence: bulk
Sender: pgsql-bugs-owner@postgresql.org

Marko Tiikkaja <marko@joh.to> writes:
> So I managed to accidentally kill and/or restart both servers while trying
> to install debug symbols, but I'm doing a new run now and I noticed
> something interesting: the listening backend's RecentXmin doesn't seem to
> ever go forward.  By my reading of this code, that would mean trouble for
> this piece of code in TransactionIdIsInProgress:

>   if (TransactionIdPrecedes(xid, RecentXmin))
>       return false;

Hmm ... I suppose it's possible that that happens if the listening
backend isn't executing any SQL commands but is just sitting.
While that might describe your test harness, does it describe any
real-world application?

			regards, tom lane


-- 
Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-bugs