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From: Madhav Madhusoodanan <madhavmadhusoodanan@gmail.com>
Date: Fri, 27 Feb 2026 02:33:22 +0530
Message-ID: <CAKw2Pb2wV=L4yeAqj27wJ1wptHt1mnBaQ5t4YuLLe+M5aU6ESg@mail.gmail.com>
Subject: Re: [WiP] B-tree page merge during vacuum to reduce index bloat
To: Kirk Wolak <wolakk@gmail.com>
Cc: Matthias van de Meent <boekewurm+postgres@gmail.com>, Andrey Borodin <x4mmm@yandex-team.ru>, 
	pgsql-hackers <pgsql-hackers@postgresql.org>, Nikolay Samokhvalov <nik@postgres.ai>
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On Tue, Aug 26, 2025 at 2:11=E2=80=AFPM Kirk Wolak <wolakk@gmail.com> wrote=
:
> I do have a question, one of the IDEAS we discussed was to ADD a new page=
 that combined the 2 pages.

Would the flow then be as follows? Please correct me if I'm wrong:
Start: Parent page P, with adjacent child pages A -> B -> C -> D.
Pages B and C are sparse enough and are about to be merged.
1: Acquire lock on pages B and C
2: Create a new page N, which copies the tuples in pages B and C
3: Acquire lock on parent page P, update the separator keys in P,
release lock on P
4: Update pointers such that pages link like so: A -> N -> D
5: Release lock on pages B and C

Regards,

Madhav