Re: Occasional tablespace.sql failures in check-world -jnn

On Tue, Dec 08, 2020 at 05:29:11PM -0800, Andres Freund wrote:
> I suspect this is related to the pg_upgrade test and the main regression
> test running at the same time. We have the following in
> src/test/regress/GNUMakefile.

Yes, this one is not completely new to -hackers.  See patch 0002 here
that slightly touched the topic by creating a specific makefile rule,
but I never got back to it as I never got annoyed by this problem:
https://www.postgresql.org/message-id/20200511.171354.514381788845037011.horikyota.ntt@gmail.com
What we have here is not a solution though...

> It's not clear to me why we have this logic in the makefile at all?
> Somebody taught pg_regress to do so, but only on windows... See
> convert_sourcefiles_in().

...  Because we may still introduce this problem again if some new
stuff uses src/test/pg_regress in a way similar to pg_upgrade,
triggering again tablespace-setup.  Something like the attached may be
enough, though I have not spent much time checking the surroundings,
Windows included.

> The other thing that confuses me is why I started getting that error in
> *multiple* branches recently, even though I have used the parallel
> check-world for ages.

Perhaps you have just increased -j lately or moved to a faster machine
where there are higher changes of collision?
--
Michael