&gt;&gt; No well, written software won&#x27;t spawn zombie-processes - sorry.
&gt; And yet it happens.<p>Strange, I have been running software in docker for almost 2 years in production on 6 docker hosts running a ton of containers these days, and yes - a lot of this software spawns child-processes.<p>In all this time I have never seen zombie processes with one major execption: Phusion Passenger to run our Redmine instance. If you run this under supervisord as &#x27;init&#x27; process -  you indeed notice the init process cleaning up &quot;zombie processes&quot; at startup like this:<p>2015-12-24 01:00:32,273 CRIT reaped unknown pid 600)
2015-12-24 01:00:34,774 CRIT reaped unknown pid 594)
2015-12-24 01:00:35,802 CRIT reaped unknown pid 610)<p>So that case for me is the exception, and I do use an init process (supervisord) to run only apache with passenger. Note that using Apache with PHP or plain does not leak zombie processes.