Date: Fri, 01 Apr 2022 13:21:57 +0900 (JST)
Message-Id: <20220401.132157.1998467224568735059.horikyota.ntt@gmail.com>
To: robertmhaas@gmail.com
Cc: alvherre@alvh.no-ip.org, michael@paquier.xyz, rjuju123@gmail.com,
 pgsql-hackers@postgresql.org
Subject: Re: standby recovery fails (tablespace related) (tentative patch
 and discussion)
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
In-Reply-To: <CA+TgmoY1rUjA+RaRug791YAtNgNeNxXtEC8ytig6LNHa9_FTug@mail.gmail.com>
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At Tue, 29 Mar 2022 09:31:42 -0400, Robert Haas <robertmhaas@gmail.com> wrote in 
> On Tue, Mar 29, 2022 at 9:28 AM Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
> > OK, this is a bug that's been open for years.   A fix can be committed
> > after the feature freeze anyway.
> 
> +1

By the way, may I ask how do we fix this?  The existing recovery code
already generates just-to-be-delete files in a real directory in
pg_tblspc sometimes, and elsewise skip applying WAL records on
nonexistent heap pages.  It is the "mixed" way.

1. stop XLogReadBufferForRedo creating a file in nonexistent
  directories then remember the failure (I'm not sure how big the
  impact is.)


2. unconditionally create all objects required for recovery to proceed..
  2.1 and igore the failures.
  2.2 and remember the failures.

3. Any other?

2 needs to create a real directory in pg_tblspc. So 1?

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center