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From: Peter Geoghegan <pg@bowt.ie>
Date: Wed, 30 Oct 2024 11:44:43 -0400
Message-ID: <CAH2-Wzki5sKPxi9OzS+ir+wHzygC5bM0+PZuTj-aXWNW1tnZiQ@mail.gmail.com>
Subject: Re: Index Partition Size Double of its Table Partition?
To: Don Seiler <don@seiler.us>
Cc: Postgres General <pgsql-general@postgresql.org>
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On Wed, Oct 30, 2024 at 11:39=E2=80=AFAM Don Seiler <don@seiler.us> wrote:
> Thanks Peter, I'll look into that shortly.

It sounds like you have no updates and deletes. Right? So the only
thing that could be different is the way that the pages are being
split (aside from variations in the width of index tuples, which seems
highly unlikely to be the only factor).

The heuristics used to trigger the relevant behavior are fairly
conservative. I wonder if we should be more aggressive about it.

> I should have also included that this is on PG 15 (currently 15.8 but we =
created the indexes when it was still 15.7) on Ubuntu 22.04 LTS.

That shouldn't matter, as far as this theory of mine is concerned.
Anything after 12 could be affected by the issue I'm thinking of.

--=20
Peter Geoghegan