Re: pg_rewind does not rewind diverging timelines

Kyotaro Horiguchi <horikyota.ntt@gmail.com>

From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
To: japinli@hotmail.com
Cc: mats.kindahl@gmail.com, suryapoondla4@gmail.com, pgsql-hackers@lists.postgresql.org
Date: 2026-06-01T06:30:58Z
Lists: pgsql-hackers
Sorry, I only just noticed this thread.

I may be missing something, but UUID feels somewhat heavyweight to me
for this problem.

I wonder whether strengthening the history-based matching would be
sufficient instead. If timelines with the same TLI but different
histories can be treated as distinct and pg_rewind continues walking
the history chain until it finds a common ancestor, that seems like a
fairly natural fit with the existing timeline model.

UUIDs would certainly make identification straightforward, although
they would also introduce longer identifiers that are a bit less
convenient for humans to work with. My initial thought is that it may
be worth exploring how far we can get with the existing history
information before introducing a new identifier.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center