Re: standby recovery fails (tablespace related) (tentative patch and discussion)

On Fri, Apr 1, 2022 at 12:22 AM Kyotaro Horiguchi
<horikyota(dot)ntt(at)gmail(dot)com> wrote:
> 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.

Can you be more specific about where we have each behavior now?

> 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?

I think we could either do 1 or 2. My intuition is that getting 2
working would be less scary and more likely to be something we would
feel comfortable back-patching, but 1 is probably a better design in
the long term. However, I might be wrong -- that's just a guess.

--
Robert Haas
EDB: http://www.enterprisedb.com