Date: Wed, 5 Jun 2024 12:45:48 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Matthias van de Meent <boekewurm+postgres@gmail.com>
Cc: Ranier Vilela <ranier.vf@gmail.com>, pgsql-hackers@postgresql.org
Subject: Re: use CREATE DATABASE STRATEGY = FILE_COPY in pg_upgrade
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On Wed, Jun 05, 2024 at 07:28:42PM +0200, Matthias van de Meent wrote:
> As for "on my laptop", that sounds very reasonable, but could you
> check the performance on systems with larger shared buffer
> configurations? I'd imagine (but haven't checked) that binary upgrade
> target systems may already be using the shared_buffers from their
> source system, which would cause a severe regression when the
> to-be-upgraded system has large shared buffers. For initdb the
> database size is known in advance and shared_buffers is approximately
> empty, but the same is not (always) true when we're doing binary
> upgrades.

Will do.  FWIW I haven't had much luck improving pg_upgrade times by
adjusting server settings, but I also haven't explored it all that much.

-- 
nathan