Red Hat

Hi,

How to get rid of Zombie Process,
Kill -9 PID does not seem to be permanent solution,

your help will be Appreciated.

Thanks

You cannot get rid of a zombie with kill and a termination signal. It is already dead, to keep the metaphor going.

Zombies are un-waited for child processes.

Instead find the parent of the process, and issue

Code:

kill -SIGCHLD [parent_pid]

This is not necessarily safe nor will it always work, if you want the parent to keep on running. The parent process signal mask could be set to terminate on SIGCHLD or do nothing. The default action for SIGCHLD is ign. The next step is to

Code:

kill -SIGTERM [parent_pid]

if the parent can be killed off.

Zombies are the result of poor coding practices.

As jim stated, a zombie process is already dead. It has already exited. Any files it opened have been closed. Any memory it allocated has been freed. Aside from its entry in the process table, its not consuming any resources. So, if you only have a few of them, it's probably not worth killing the parent or rebooting.

Again, as jim stated, zombies are the result of a parent not looking after its children. If the parent's code is under your control, you should improve it with the appropriate wait calls. If it is not, you should file a bug report with the author.

Regards,
Alister

even killing Parent_PID, is not working,
any other work around to make this work..

Thanks

If you killed the parent and it has exited, and if the zombie process is still hanging around, then it is not a zombie process (which wouldn't suprse me because "zombie" is an often misused term).

Provide two reports of the "zombie" processes and their parents, one before and one after killing a parent, using a ps format which at the very least includes uid, pid, ppid, and stat. Also, include the output of the id command when run by the same user that kills the parent.

Regards,
Alister

We need to see the output of ps -ef showing the parent and the zombie(s). If you actually terminated the parent, the zombies would also "go away" in a few minutes. If you terminated another non-parent then, no, the zombies will remain.

These are the outputs requested, i have killed the PPID, will post the out puts again if the Zombie process comes up again,

Code:

[cmsprod@drcmsapp303 lib]$ id
uid=2049(cmsprod) gid=2049(cmsprod) groups=200(oinstall),2049(cmsprod),4061(varlogs)
[cmsprod@drcmsapp303 lib]$ ps axo stat,ppid,pid,comm | grep -w defunct
Z    13464 19966 java <defunct>
[cmsprod@drcmsapp303 lib]$ kill -SIGCHLD 13464
[cmsprod@drcmsapp303 lib]$ kill -SIGTERM 13464
[cmsprod@drcmsapp303 lib]$ ps axo stat,ppid,pid,comm | grep -w defunct
[cmsprod@drcmsapp303 lib]$

Thanks