[libvirt] Zombie process after open libvirt connection

[Michal Privoznik]

On 17.03.2014 11:13, Carlos Rodrigues wrote:
> Hello,
>
> Does anyone can help me? I a need a solution for this, 'cause i have a
> process/daemon, it reaches about 200 zombie processes, after open a new
> libvirt connection with qemu+tls.
>
> Best regards,
>

 From the script you've attached:

     $SIG{'CHLD'} = sub { print "receive chld","\n"; };

You should either waitpid() child here or at the end of the script. The 
former approach won't leave any zombies hanging around, the latter 
requires you to keep return values of fork(). So I think your script 
needs to look like this:

$ diff -up test-chldhandle-bug.pl test-chldhandle-bug-fixed.pl
--- test-chldhandle-bug.pl   2014-03-17 11:59:48.972238074 +0100
+++ test-chldhandle-bug-fixed.pl     2014-03-17 12:03:08.693875968 +0100
@@ -5,10 +5,12 @@ use strict;

  use Sys::Virt;
  use POSIX qw(:signal_h);
+use POSIX ":sys_wait_h";

  sub main {
      print "init... pid=$$","\n";
-    $SIG{'CHLD'} = sub { print "receive chld","\n"; };
+    $SIG{'CHLD'} = sub { my $kid; print "receive chld","\n";
+        do { $kid = waitpid(-1, WNOHANG); } while $kid > 0; };

      while(1){
                 print "while...","\n";


Michal