Message-ID: <3ee88744547f6865fe2f48b2b6f058a50796cb91.camel@j-davis.com>
Subject: Re: Proposal to add page headers to SLRU pages
From: Jeff Davis <pgsql@j-davis.com>
To: "Li, Yong" <yoli@ebay.com>, Aleksander Alekseev
 <aleksander@timescale.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, "Bagga, Rishu"
 <bagrishu@amazon.com>, Robert Haas <robertmhaas@gmail.com>, "Debnath,
 Shawn" <sdn@ebay.com>, Andrey Borodin <x4mmm@yandex-team.ru>, "Shyrabokau,
 Anton" <antons@ebay.com>
Date: Fri, 08 Mar 2024 13:22:30 -0800
In-Reply-To: <4B689BA2-270F-4B26-AAA2-65BB17C03AC4@ebay.com>
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On Wed, 2024-03-06 at 12:01 +0000, Li, Yong wrote:
> Rebase the patch against the latest HEAD.

The upgrade logic could use more comments explaining what's going on
and why. As I understand it, it's a one-time conversion that needs to
happen between 16 and 17. Is that right?

Was the way CLOG is upgraded already decided in some earlier
discussion?

Given that the CLOG is append-only and gets truncated occasionally, I
wonder whether we can just have some marker that xids before some
number are the old CLOG, and xids beyond that number are in the new
CLOG. I'm not necessarily suggesting that; just an idea.

Regards,
	Jeff Davis