Re: pg_stop_backup does not complete

> If you like the concept, then the next question is exactly how to phrase
> the messages.  All we have at the moment is the inside-the-delay-loop
> warning:
> 
>     ereport(WARNING,
>             (errmsg("pg_stop_backup still waiting for archive to complete (%d seconds elapsed)",
>                     waits)));

Well, we'll want this message first, as soon as pg_stop_backup finishes
checkpointing:

WARNING: Stop backup work complete.  Now awaiting completion of WAL
archiving.

Then after 60s:

WARNING: pg_stop_backup is still waiting for WAL archiving to complete
(%d seconds elapsed).
HINT: Check if your WAL archive_command is failing.  You may abort
pg_stop_backup at this point, but you will not be able to use the
resulting clone.