Feedback-ID: i0fe9450f:Fastmail
Date: Thu, 12 Oct 2023 16:27:19 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, Dilip Kumar <dilipbalaut@gmail.com>,
	Heikki Linnakangas <hlinnaka@iki.fi>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: New WAL record to detect the checkpoint redo location
Message-ID: <ZSef15UpksauWnbU@paquier.xyz>
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On Tue, Oct 10, 2023 at 02:43:34PM -0400, Robert Haas wrote:
> - I combined what were previously 0002 and 0003 into a single patch,
> since that's how this would get committed.
>=20
> - I fixed up some comments.
>=20
> - I updated commit messages.
>=20
> Hopefully this is getting close to good enough.

I have looked at 0001, for now..  And it looks OK to me.

+        * Nonetheless, this case is simpler than the normal cases handled
+        * above, which must check for changes in doPageWrites and RedoRecP=
tr.
+        * Those checks are only needed for records that can contain
+        * full-pages images, and an XLOG_SWITCH record never does.
+        Assert(fpw_lsn =3D=3D InvalidXLogRecPtr);

Right, that's the core reason behind the refactoring.  The assertion
is a good idea.
--
Michael

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