Feedback-ID: id4a34324:Fastmail
Date: Wed, 1 Oct 2025 09:49:10 -0400
From: Andres Freund <andres@anarazel.de>
To: Laurenz Albe <laurenz.albe@cybertec.at>
Cc: Frits Hoogland <frits.hoogland@gmail.com>,
	Aleksander Alekseev <aleksander@tigerdata.com>,
 pgsql-hackers@lists.postgresql.org
Subject: Re: The ability of postgres to determine loss of files of the main
 fork
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Hi,

On 2025-10-01 15:39:04 +0200, Laurenz Albe wrote:
> On Wed, 2025-10-01 at 13:58 +0200, Frits Hoogland wrote:
> > I am proposing the database to have the ability to detect when it has missing segments.
> 
> Just a random idea: one solution would be if each segment has a flag that indicates
> if that is the last segment or not.  But that would break the on-disk storage format,
> unless there is room left for an extra flag somewhere in the current layout.

It'd also make extensions / truncations more complicated. I rather doubt we're
going there. Right now relation extension aren't WAL logged. While there might
be reasons to change that, I don't think this is enough justification for
doing so.

Greetings,

Andres