Re: allowing VACUUM to be cancelled for conflicting locks

Andres Freund <andres@2ndquadrant.com> writes:
> I don't think this is about the truncation thing, but about the
> deadlock.c/proc.c logic around DS_BLOCKED_BY_AUTOVACUUM. I.e. that a
> autovacuum is cancelled if user code tries to acquire a conflicting
> lock.

It's a bit of a stretch to claim that a manual VACUUM should be cancelled
by a manual DDL action elsewhere.  Who's to say which of those things
should have priority?
        regards, tom lane