From: Tom Lane <tgl@sss.pgh.pa.us>
To: vignesh C <vignesh21@gmail.com>
cc: Alexander Korotkov <aekorotkov@gmail.com>,
        "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>,
        Alexander Lakhin <exclusion@gmail.com>,
        Vitaly Davydov <v.davydov@postgrespro.ru>,
        Amit Kapila <amit.kapila16@gmail.com>,
        pgsql-hackers <pgsql-hackers@postgresql.org>,
        Masahiko Sawada <sawada.mshk@gmail.com>,
        "tomas@vondra.me" <tomas@vondra.me>
Subject: Re: Slot's restart_lsn may point to removed WAL segment after hard
 restart unexpectedly
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Comments: In-reply-to vignesh C <vignesh21@gmail.com>
	message dated "Tue, 17 Jun 2025 08:24:41 +0530"
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Date: Tue, 17 Jun 2025 16:18:30 -0400
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vignesh C <vignesh21@gmail.com> writes:
> While tracking buildfarm for one of other commits, I noticed this failure:
> TRAP: failed Assert("s->data.restart_lsn >=
> s->last_saved_restart_lsn"), File:
> "../pgsql/src/backend/replication/slot.c", Line: 1813, PID: 3945797

My animal mamba is also showing this assertion failure, but in a
different test (recovery/t/040_standby_failover_slots_sync.pl).
It's failed in two out of its three runs since ca307d5ce went in,
so it's more reproducible than scorpion's report, though still not
perfectly so.

I suspect that mamba is prone to this simply because it's slow,
although perhaps there's a different reason.  Anyway, happy to
investigate manually if there's something you'd like me to
check for.

			regards, tom lane