On 2015-10-12 10:04:55 -0400, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > On 2015-10-12 21:38:12 +0900, Michael Paquier wrote:
> >> Actually, doesn't this apply as well to the archiver and the pgstat
> >> collector?
>
> > As mentioned above? The difference is that the archiver et al get killed
> > by postmaster during a PANIC restart thus don't present the problem
> > discussed here.
>
> I thought your objection to the original patch was exactly that we should
> not treat syslogger as a special case for this purpose.
Yes. The above was just about this not being actively broken - I'd
mentioned the other processes before and to me it sounded like Michael
thought there might be an active problem.
> > Well, in those cases we won't have attached to shared memory, so I'm not
> > convinced that this is the right solution.
>
> No, you're missing the point.
Don't think so.
> In Windows builds, child processes inherit
> a "handle" reference to the shared memory mapping, whether or not they
> make any use of the handle to re-attach to that shared memory. The point
> here is that we need to close that handle if we're not going to use it.
Right. But that doesn't mean it's right to call PGSharedMemoryDetach()
without other changes as done in Michael's proposed patch? That'll do an
UnmapViewOfFile() which'll fail because nothing i mapped, but still not
close UsedShmemSegID?
Greetings,
Andres Freund
