Re: cannot drop replication slot if server is running in single-user mode

Alvaro Herrera wrote:
> Robert Haas wrote:
> > On Thu, Mar 29, 2018 at 5:51 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> > >> > 2018-03-06 13:20:24.391 GMT [14869] ERROR: epoll_ctl() failed: Bad file
> > >> > descriptor
> > >>
> > >> I can confirm this bug exists in single-user mode.
> > >
> > > I'm not sure we need to do anything about this, personally. This seems
> > > like a fairly rare thing to do in a mode that's definitely not intended
> > > to be general purpose.
> >
> > Mmmph. I don't really think it's possible to view a user-visible
> > EBADF as anything other than a coding error.
>
> IMO the problem is not the user-visible EBADF -- the problem is that the
> user might be attempting to clean up from some previous mistake by
> removing a replication slot. Using single-user mode might be a strange
> tool, but it's not completely unreasonable. Is it really all that
> difficult to fix slot acquisition for it?

Here's a patch (against pg10) to fix this problem.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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