[Users] Question about forking

[Anatoly Pidruchny]

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
>> >
>>
>>
>