Date: Tue, 8 Jul 2025 16:06:16 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Hannu Krosing <hannuk@google.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Horribly slow pg_upgrade performance with many Large Objects
Message-ID: <aG2ISJC__3lQwRqY@nathan>
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On Sun, Jul 06, 2025 at 02:48:08PM +0200, Hannu Krosing wrote:
> Did a quick check of the patch and it seems to work ok.

Thanks for taking a look.

> What do you think of the idea of not dumping pg_shdepend here, but
> instead adding the required entries after loading
> pg_largeobject_metadata based on the contents of it ?

While not dumping it might save a little space during upgrade, the query
seems to be extremely slow.  So, I don't see any strong advantage.

-- 
nathan