Zombie process question!!!

[Jack Fan]

All,
I wondering that why we get in zombie process?
My server broadcast some message with wall command on crontab everyday. But since early day, the wall process become zombie process. I can not kill them. If reboot server is the only way?

regards,
Jack Fan

[Michael Tully]

Hi,

Unless the process can be killed with a -9 option, the only way to kill it is to reboot your server. Unless the process consuming all of your CPU (single processor machine) try to schedule the reboot for your lunch-time or even after hours.

# kill -9 1234

These processes are already dead but haven't been released by the process table. DO NOT KILL THE PARENT OF A ZOMBIE, i.e. process ID 1.

If the problem persists have a look at installing a later patch bundle.

Michael

[Jack Fan]

Sir, thanks for your reply. But I still wondering that,

1. What is the root cause of zombie process?
2. If any latest patch to solve this problem?
3. What is its frequency?
Thanks in advance.

Regards,
Jack Fan

[Michael Tully]

Hi Jack,

The root cause of a zombie is where a process dies (child) before the parent has actually released it, hence still being in the process table. There are patches released all the time, that fix these type of issues, if it is the fault of the operating system. Generally these happen due to bad coding from applications. The frequency, well this depends on how good the application is.

Hope this explains it....

Cheers
~Michael~

[Jack Fan]

Michael,
Can you tell me the latest patch ID which able to fix "Zombie" process" problem. OR I need call local HP engineer to do patch management. However, thanks for your technical explaining and feedback.

Regards,
Jack Fan

[Michael Tully]

Hi Jack,

The problem where zombies could occur will be in a variety of programs. I suggest you look at installing the latest patch bundle as opposed to individual patches.

Here is a good starting point
http://www.software.hp.com/SUPPORT_PLUS/

or you can start from here and order them
providing you have a support contract.

http://us-support2.external.hp.com/common/bin/doc.pl/distrib_redir=1+985580381|*

Please make sure that you try to award points to people that assist you.

Cheers
~Michael~