Date: Thu, 6 Mar 2025 13:44:30 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Noah Misch <noah@leadboat.com>
Cc: Michael Paquier <michael@paquier.xyz>,
	Andres Freund <andres@anarazel.de>,
	Robert Pang <robertpang@google.com>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	Tom Lane <tgl@sss.pgh.pa.us>, robertmhaas@gmail.com,
	pgsql-hackers@postgresql.org
Subject: Re: Back-patch of: avoid multiple hard links to same WAL file after
 a crash
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On Thu, Mar 06, 2025 at 11:30:13AM -0800, Noah Misch wrote:
> Options I see:
> 
> 1. Make v14 and v13 skip WAL recycling and preallocation during archive
>    recovery, like newer branches do.  I think that means back-patching the six
>    commits cc2c7d6~4 cc2c7d6~3 cc2c7d6~2 cc2c7d6~1 cc2c7d6 e36cbef.
> 
> 2. Revert 1f95181b44c843729caaa688f74babe9403b5850 and its v13 counterpart.
>    Avoid multiple hard links by making durable_rename_excl() first rename
>    oldfile to a temporary name.  (I haven't thought this through in detail.
>    It may not suffice.)
> 
> I'm leaning toward (1) at least enough to see how messy the back-patch would
> be, since I don't like risks of designing old-branch-specific solutions when
> v15/v16/v17 have a proven solution.  What else should we be thinking about
> before deciding?

I agree with first attempting a back-patch.  All of this stuff is from
2021-2022, so it's had time to bake and is IMHO lower risk.

-- 
nathan