[erlang-questions] Scoped group leaders

[Eric Merritt]

I am talking about the situation where no process that where once part
of the group exist any longer. When a group has no processes, the
group no longer exists, however the memory alloced by this will
continue to exist, thats the problem.

On Tue, Jul 5, 2011 at 6:04 PM, Robert Virding
<robert.virding@REDACTED> wrote:
> Conceptually a process is always the member of a group so the very idea of removing a group leader from a process does not make sense. All you can do is assign it another group leader.
>
> Robert
>
> ----- "Eric Merritt" <ericbmerritt@REDACTED> wrote:
>
>> I wouldn't expect in in the prototype. I am more thinking of the end
>> result.
>>
>> On Tue, Jul 5, 2011 at 10:31 AM, Yurii Rashkovskii <yrashk@REDACTED>
>> wrote:
>> > Right now there is no way to remove a group leader from process,
>> but
>> > it is not inherently impossible to do so, just was out of scope of
>> > this prototype.
>> >
>> > On Tue, Jul 5, 2011 at 8:05 AM, Eric Merritt
>> <ericbmerritt@REDACTED> wrote:
>> >> I understand and that makes sense, but it does raise a potential
>> >> problem. That is group leaders are created but never destroyed. In
>> the
>> >> case of the process itself, this is probably ok. The developer
>> will
>> >> have to create some mechanism to know when his group leader is no
>> >> longer useful and have it die on its own. However, I didn't see
>> any
>> >> mechanisms to unregister group leaders and reclaim the memory
>> alloced
>> >> when they are created. That could be me missing something when I
>> was
>> >> looking at the code, if so then the point is moot, however if not
>> >> that's something that would probably need to be added to make this
>> >> workable. Of course, that still leaves the problem that if a group
>> >> leader dies unexpectedly, or the user mis-codes his application
>> and
>> >> forgets to unregister a group leader when it dies, then he has a
>> >> memory leak. You could say that its a users problem and go from
>> there,
>> >> but leaving around unreferenced memory just doesn't smell right.
>> (I
>> >> know, we do that already with the atom table, but it doesn't make
>> it a
>> >> good thing)
>> >>
>> >> On Mon, Jul 4, 2011 at 6:57 PM, Robert Virding
>> >> <robert.virding@REDACTED> wrote:
>> >>> ----- "Eric Merritt" <ericbmerritt@REDACTED> wrote:
>> >>>
>> >>>> >
>> >>>> >
>> >>>> >> Just out of curiosity does a group leader go away when a
>> group
>> >>>> dies?
>> >>>> >
>> >>>> > Define group death?
>> >>>> >
>> >>>>
>> >>>> When when all processes in a group have terminated, either
>> normally
>> >>>> or
>> >>>> abnormally.
>> >>>
>> >>> Today there is nothing in the system which keeps track of the
>> processes in a group, process groups don't really exist at all. A
>> "process group" is those processes which have the same group leader.
>> The group leader has no information about which processes have it as
>> group leader. You can make any process a group leader by setting it as
>> group leader.
>> >>>
>> >>> Process groups were explicitly added in such a way as NOT to
>> impose any structure or hierarchy on processes, process space is
>> flat.
>> >>>
>> >>> Robert
>> >>>
>> >>
>> >
>