[Users] Question about forking

Tim Madorma tmadorma at gmail.com
Wed May 16 19:59:45 CEST 2007


Hi Anatoly,

That is what I did in the first example that I sent to you today.
Running manually with the -D option has the same results as when
executing openser with runsv.

thanks,

Tim

On 5/16/07, Anatoly Pidruchny <apidruchny at newxt.com> wrote:
> Tim,
>
> I can not explain why it behaves differently. But can you also try the
> same test with -D option, but without using runsv?
>
> Anatoly.
> > Hi Anatoly,
> >
> > Thanks for your work-around - I'll try it. However, I did try the test
> > you described without the -D option and here are the results:
> >
> > root at homer:/# ps -ef | grep openser
> > sipproxy 29793 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29788 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29791 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29789 29786   0 12:52:24 ?           0:00 openser
> > root 29797 29266   0 12:52:28 pts/1       0:00 grep openser
> > sipproxy 29795 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29786     1   0 12:52:24 ?           0:00 openser
> > sipproxy 29794 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29792 29786   0 12:52:24 ?           0:00 openser
> > sipproxy 29790 29787   0 12:52:24 ?           0:00 openser
> > sipproxy 29787 29786   0 12:52:24 ?           0:00 openser
> >
> > root at homer:/# kill 29786
> > root at homer:/# ps -ef | grep openser
> >    root 29799 29266   0 12:52:50 pts/1       0:00 grep openser
> >
> > As you can see, the child (29787) kills the grandchild (29790) when
> > the parent (29786) is killed. I'm not sure why it behaves differently.
> >
> > Tim
> >
> > On 5/16/07, Anatoly Pidruchny <apidruchny at newxt.com> wrote:
> >> Hi Tim,
> >>
> >> As far as I know, the problem with the left over openser process that
> >> you described is not caused by the patch. If you run openser manually
> >> without -D option, then kill the main process, you will get exactly the
> >> same result. The main openser process will kill all its children, but
> >> will not kill its grandchildren. The reason is that the main openser
> >> process does not know anything about its grandchildren. Theoretically,
> >> the process that forked a child (for example, your process with PID
> >> 29744) is supposed to kill its children (for example, your process with
> >> PID 29747) when it is terminated. But this does not happen. I think it
> >> is a known issue (bug?) with openser. May be if you open a feature (or
> >> bug?) request then this issue will be resolved.
> >>
> >> By the way, we do not have this problem. I think the reason is that you
> >> use some module that we do not use. I grepped the openser sources and
> >> found a number of places in modules where a child process is forked. In
> >> our case, I think we never hit code that creates any of the "child of a
> >> child" processes.
> >>
> >> As a workaround, did you try to kill all the left over openser processes
> >> from the ./finish file?
> >>
> >> Regards,
> >>
> >> Anatoly.
> >> > Hey Anatoly,
> >> >
> >> > I've been running with your patch and it works, but there is one issue
> >> > that I want to bring up. After openser forks, it creates processes as
> >> > follows:
> >> >
> >> > sipproxy 29745 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29751 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29748 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29750 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29743 29432   0 11:32:37 pts/2       0:00 openser -D
> >> > sipproxy 29752 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29744 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29746 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29749 29743   0 11:32:38 pts/2       0:00 openser -D
> >> > sipproxy 29747 29744   0 11:32:38 pts/2       0:00 openser -D
> >> >
> >> > You can note that the parent PID is 29743 and has several children,
> >> > but for some reason, process 29744 also spawns the child process
> >> > 29747. When I use runsv to start the process, it notes the process
> >> > that it creates is 29743. Then when I terminate with runsv, it kills
> >> > 29743 - which kills all of it's children, but leaves PID 29747
> >> > running. Since it's parent was killed, PID 29747 is adopted by the
> >> > init process (PID 1). Here is an example of this done by hand (with a
> >> > kill of 29743):
> >> >
> >> > root at homer:/# kill 29743
> >> > root at homer:/# ps -ef | grep openser
> >> >    root 29756 29266   0 11:35:19 pts/1       0:00 grep openser
> >> > sipproxy 29747     1   0 11:32:38 pts/2       0:00 openser -D
> >> >
> >> > Please let me know if you can assist here.
> >> >
> >> > thanks much,
> >> > Tim
> >> >
> >> > On 5/7/07, Anatoly Pidruchny <apidruchny at newxt.com> wrote:
> >> >> Hi, Tim,
> >> >>
> >> >> there is a patch (that I submitted) that allows to run the main
> >> openser
> >> >> process in foreground and fork child processes as usual. No developer
> >> >> has reviewed the patch yet. I hope this patch will be accepted
> >> soon. The
> >> >> patch is simple and we use it for a long time now. You can also
> >> take the
> >> >> patch and use it.
> >> >>
> >> >> The patch is:
> >> >>
> >> http://sourceforge.net/tracker/index.php?func=detail&aid=1689998&group_id=139143&atid=743022
> >>
> >> >>
> >> >>
> >> >> Anatoly
> >> >> > Hi,
> >> >> >
> >> >> > I want to start openser with runsv which requires that the starting
> >> >> > process run in the foreground. My problem is that I also want to
> >> >> > listen on a couple of different ports. When I set forking = yes, it
> >> >> > will listen on multiple ports, but runsv won't work. When I set
> >> >> > forking=no, then openser will only listen on the first specified
> >> port.
> >> >> >
> >> >> > Is there any way around this? Can I have the starting process
> >> run in
> >> >> > the foreground and fork other processes that listen to the ports in
> >> >> > the background?
> >> >> >
> >> >> > Here is the error message:
> >> >> >
> >> >> > WARNING: no fork mode  and more than one listen address
> >> found(will use
> >> >> > only the the first one)
> >> >> >
> >> >> > Here are the associated configuration lines:
> >> >> >
> >> >> > fork=no
> >> >> >
> >> >> > children=32
> >> >> >
> >> >> > # Local IP address/port pairs to listen to
> >> >> > listen=65.185.233.55:5061
> >> >> > listen=65.185.233.55:5062
> >> >> >
> >> >> > # Alias IP address/port pairs
> >> >> > alias=65.185.233.104:5061
> >> >> > alias=65.185.233.104:5062
> >> >> >
> >> >> > thanks,
> >> >> > Tim
> >> >> >
> >> >> > _______________________________________________
> >> >> > Users mailing list
> >> >> > Users at openser.org
> >> >> > http://openser.org/cgi-bin/mailman/listinfo/users
> >> >> >
> >> >>
> >> >>
> >> >
> >>
> >>
> >
>
>




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