supervisord stopping child processes

Question

One of the problems, I face with supervisord is that when I have a command which in turn spawns another process, supervisord is not able to kill it.

For example I have a java process which when runs normally is like

 $ zkServer.sh start-foreground
 $ ps -eaf | grep zk
 user 30404 28280  0 09:21 pts/2    00:00:00 bash zkServer.sh start-foreground
 user 30413 30404 76 09:21 pts/2    00:00:10 java -Dzookeeper.something..something

The supervisord config file looks like:

[program:zookeeper]
command=zkServer.sh start-foreground
autorestart=true
stopsignal=KILL

These kind of processes which have multiple childs are not well handled by supervisord when it comes to stopping them from supervisorctl. So when I run this from the supervisord and try to stop it from supervisorctl, only the top level process gets killed but not the actual java process.

It is my understanding that the [`systemd`](http://en.wikipedia.org/wiki/Systemd) `init`-replacement's use of [`cgroups`](http://en.wikipedia.org/wiki/Cgroups) allows for reliably tracking child processes. It might be suitable for your needs. — sarnold, Feb 01 '12 at 04:14

score 114 · Answer 1 · answered Dec 13 '13 at 12:10

114

The same problem was encountered by Rick Hanlon II here: https://coderwall.com/p/4tcw7w

Option stopasgroup=true should be set in the program section for supervisord to stop not only the parent process but also the child processes.

The example is given as:

[program:some_django]
 command=python manage.py runserver
 directory=/dir/to/app
 stopasgroup=true

Also, have in mind that you may have an older package of supervisord that does not have "stopasgroup" functionality. I tried these Debian packages on Raspberry Pi:

supervisor_3.0a8 does not work.
supervisor_3.0b2-1 works as expected.

answered Dec 13 '13 at 12:10

kuzavas

2,156
1
16
8

8

Also note that supervisord doesn't take configuration changes automatically. You'll need to run `supervisorctl update` to apply changes to your configuration, or restart the supervisord process. – jjmontes Aug 24 '16 at 20:16
6

This should really be the default option. – Shubham Chaudhary Feb 01 '17 at 06:20
3

This worked perfectly for me with supervisor 3.2. Thanks. – Cerin Jan 05 '18 at 16:47

score 14 · Answer 2 · answered Mar 12 '14 at 21:15

14

Doing the following early in the main bash script called by supervisord fixed the problem for me:

trap "kill -- -$$" EXIT

This kills the entire process group when the main script exits, such as when it is killed by supervisord.

answered Mar 12 '14 at 21:15

Fred Yankowski

684
1
8
12

score 7 · Answer 3 · answered Jun 28 '18 at 06:36

7

try this supervisor program config:

stopasgroup=true
killasgroup=true
stopsignal=INT

answered Jun 28 '18 at 06:36

Color

875
9
11

score 6 · Answer 4 · answered Feb 01 '12 at 19:18

6

A feature was recently added to supervisord to send SIGKILL to the whole process group. It's in github but not officially released yet.

If the process id is available in a file, you can use the pid-proxy program

answered Feb 01 '12 at 19:18

Roger Hoover

596
4
5

score 4 · Answer 5 · answered Jan 11 '15 at 19:31

4

The following article has an in-depth discussion of the problem:

http://veithen.github.io/2014/11/16/sigterm-propagation.html

answered Jan 11 '15 at 19:31

Andreas Veithen

8,868
3
25
28

exec ... solved it for me. The first option in the article. Thanks – Alon Catz Aug 08 '15 at 10:25
1

Thank you for teaching how to catch the fish instead of supplying it ;) – Gökçer Gökdal Oct 11 '17 at 14:25

score 0 · Answer 6 · answered Nov 05 '16 at 02:35

0

You can also use priorities in /conf.d/your-configuration.conf file. For example, if you want to run zookeeper first and then kafka you can specify two programs.

Lower priority means that the program starts first and stops last.

answered Nov 05 '16 at 02:35

baqx0r

105
1
2
11

supervisord stopping child processes

6 Answers6

Linked