Killing Zombies through scripts

[Doug_85]

Running on HP-UX 11.0
L class server

Is there a way you can kill zombie processes without restarting the system? I was thinking about creating a shell script that finds the processes and kills them a couple times each day through the crontab. Any suggestions? Below is a partial script I thought I might use. I may try it with -11 or -14 instead of the -9 though.

ps -f |grep |kill -9

Any suggestions?

Thanks,
Doug

[Mel Burslan]

Doug,

The term zombie process is derived affectionately based on the same concept of bodies which can not die. So, the short answer to your question is no. There is no way to kill a zombie process in short of a reboot.

Having said that, not all processes can be put into the zombie class. Some will disappear from the process listings after a while.

If you are having issues with too many zombie processes are hanging around, you may need to get to the bottom of the problem and talke to the developers of the software running on your system if it is internal or call the vendor and ask for their suggestion if this is a package purchased form them.

Sorry to be the bearer of the bad news.

[Jeff Schussele]

Hi Doug,

As stated you *CAN'T* kill a zombie - BECAUSE THEY'RE ALREADY DEAD!!!!

That being said - IF they've been inherited - as a parent by init - PID #1 - then it has routines to reap it's children periodically.
IF they still have the org parent PID, then someone - in development - needs to go back to coding school. That's just lazy, lousy programming - period. In that case a stout hickory handle seems to work best for me.....

My 2 cents,
Jeff

[PAVIC Thierry · Accepted solution]

Try this script, it will kill all defunct process if there is no dependent link with a father zombie




#!/bin/ksh
# --------------------------------------------------------------------------
# Fichier : Exp_KillPsDefunct.sh
# Action : Suppresion des process zombies
# Entree :
# Sortie :
# Usage :
# --------------------------------------------------------------------------
# Maintenance
# Date Auteur Action
# --------------------------------------------------------------------------
# 13/07/2004 TPA Creation
# --------------------------------------------------------------------------
#set -x
L_FicLst=/tmp/exploit/tmp/Exp_KillPsDefunct.txt
L_FicShell=/tmp/exploit/tmp/Exp_KillPsDefunct.sh
L_FicLog=/tmp/exploit/log/Exp_KillPsDefunct.log


# -- Raz
cat /dev/null > ${L_FicLst}
cat /dev/null > ${L_FicLog}

echo " -----------------------------------------------------------------" >> ${L_FicLog}
L_NbPs=`ps -ef |grep defunct|grep -v grep |wc -l`
echo "Nombre de process defunct : ${L_NbPs}">> ${L_FicLog}

echo " -----------------------------------------------------------------" >> ${L_FicLog}
echo "- Action : `date +%H:%M:%S` : Constitution de la liste des process" >> ${L_FicLog}
echo " -----------------------------------------------------------------" >> ${L_FicLog}
ps -ef |grep defunct|grep -v grep > ${L_FicLst}
cat ${L_FicLst} >> ${L_FicLog}

echo " -----------------------------------------------------------------" >> ${L_FicLog}
echo "- Action : `date +%H:%M:%S` : Constitution du shell" >> ${L_FicLog}
echo " -----------------------------------------------------------------" >> ${L_FicLog}
cat ${L_FicLst} |awk '{printf "kill -9 " $2 "\n"}' > ${L_FicShell}
cat ${L_FicShell} >> ${L_FicLog}

echo " -----------------------------------------------------------------" >> ${L_FicLog}
echo "- Action : `date +%H:%M:%S` : Constitution du shell" >> ${L_FicLog}
echo " -----------------------------------------------------------------" >> ${L_FicLog}
chmod 777 ${L_FicShell}

${L_FicShell} >> ${L_FicLog}

echo " -----------------------------------------------------------------" >> ${L_FicLog}
L_NbPs=`ps -ef |grep defunct|grep -v grep |wc -l`
echo "Nombre de process defunct : ${L_NbPs}">> ${L_FicLog}

[YoungHwan, Ko]

Defunct and zomnbie processor is not running processor with resource.
If it is not removed until the system reboot. moreover it will have resource.
It have little effect using kill command.
This is normal state. When the processor halt, it will remain in defunct state. But it occupy little space than address territory.
If you sent signal to processor, which is already halt, you cannot have an influence on it. this proccessor will remove when the proccessor stop, and it will remain defunct processor until system reboot.
For more information refer to 'kill' and 'wait' man page.

And if you want to know system's cpu consumption use this command.
# UNIX95= ps -e -o "user,pcpu,args" | sort -rnk2 | more

Aagin And this problem may solve to upgrade support plus in lastest version.
download site is below.
http://www2.itrc.hp.com/service/patch/releaseIndexPage.do?BC=patch.breadcrumb.main

[Geoff Wild]

Used to be able to kill most zombiew with:

logfile=/tmp/killzombies.log

for i in `ps -el|grep -v SZ|grep Z|awk '{print $5}'`
do
ps -ef|grep -v grep|grep ${i} >>$logfile 2>&1
kill -18 ${i}
done

Rgds...Geoff

[twang]

In my past experience, zombie cannot be killed except reboot!