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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Justin Pryzby <pryzby@telsasoft.com>
cc: pgsql-hackers@postgresql.org
Subject: Re: v16dev: TRAP: failed Assert("size > SizeOfXLogRecord"),
 File: "xlog.c", Line: 1055, PID: 13564
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Comments: In-reply-to Justin Pryzby <pryzby@telsasoft.com>
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Date: Mon, 17 Apr 2023 11:16:30 -0400
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Justin Pryzby <pryzby@telsasoft.com> writes:
> I hit this assertion while pg_restoring data into a v16 instance.
> postgresql16-server-16-alpha_20230417_PGDG.rhel7.x86_64

> wal_level=minimal and pg_dump --single-transaction both seem to be
> required to hit the issue.

Hmm.  I wonder if log_newpages() is confused here:

	XLogEnsureRecordSpace(XLR_MAX_BLOCK_ID - 1, 0);

Why is XLR_MAX_BLOCK_ID - 1 enough, rather than XLR_MAX_BLOCK_ID?

			regards, tom lane