From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Matthias van de Meent <boekewurm+postgres@gmail.com>,
        Justin Pryzby <pryzby@telsasoft.com>, pgsql-hackers@postgresql.org
Subject: Re: v16dev: TRAP: failed Assert("size > SizeOfXLogRecord"),
 File: "xlog.c", Line: 1055, PID: 13564
In-reply-to: <2444561.1681748021@sss.pgh.pa.us>
References: <ZD1daibg4RF50IOj@telsasoft.com>
 <CAEze2Wg+Pbec3jaaUSF8E6Piy=bq=gXkFCFyaYwFDYTDjCMSvg@mail.gmail.com>
 <2444561.1681748021@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Mon, 17 Apr 2023 12:13:41 -0400"
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Date: Mon, 17 Apr 2023 13:50:30 -0400
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I wrote:
> Yeah, I just came to the same conclusion.  One thing I don't understand
> yet: log_newpage_range is old (it looks like this back to v12), and
> that Assert is older, so why doesn't this reproduce further back?
> Maybe the state where all the pages are new didn't happen before?

Bingo: bisecting shows the failure started at

commit 3d6a98457d8e21d85bed86cfd3e1d1df1b260721
Author: Andres Freund <andres@anarazel.de>
Date:   Wed Apr 5 08:19:39 2023 -0700

    Don't initialize page in {vm,fsm}_extend(), not needed

So previously, log_newpage_range could only have failed in very
unlikely circumstances, whereas now it's not hard to hit when
committing a table creation.  I wonder what other bugs may be
lurking.

I'll patch it back to v12 anyway, since that function is
clearly wrong in isolation.

			regards, tom lane