topic zombie and/or orphan in Operating System - HP-UX

zombie and/or orphan

Marty Metras — Fri, 04 May 2001 19:56:56 GMT

How do I find a zombie and/or orphan.
Our HP 9000 with HP-UX 10.20 is getting slow because we need to update to a new box.
While I'm waiting for them to OK the money I have to keep thing running as fast as I can.
I use top to see what is going and today I see I have a zombie.
I know what a zombie is. What I dont know is how to find it.
I have killed processes that were on tot of top. These have very log process times and and are connected to PID 1 as there parent and belong a users I can deal with.
How do I find a zombie that is showing like this?
-----------------------------
System: Marty_box1 Fri May 4 15:33:45 2001
Load averages: 0.88, 1.36, 2.06
254 processes:
252 sleeping, 1 running, 1 zombie
----------------
Marty

Re: zombie and/or orphan

A. Clay Stephenson — Fri, 04 May 2001 20:02:07 GMT

Hi Marty:
Rule Number 1, You can't kill a zombie - it's already dead. The system will usually remove them (actually clean the process table) but it takes a while.

If you can avoid it don't kill with a kill -9. You clobber all it's cleanup. Try to kill with a kill -11; it's almost as good and does much better process cleanup before exit.

Regards, Clay

Re: zombie and/or orphan

A. Clay Stephenson — Fri, 04 May 2001 20:08:17 GMT

Oops, I signed off too quickly.

Performance is much more impacted by runaway processes. Those are what you need to look out for. Of course, finding an actual runaway process is not always easy - it might be a perfectly valid process; you need to know your environment. But in the case of runaway processes if you kill first with a kill -15 (the normal); then kill -11; and finally kill -9 you will greatly reduce the zombie's and orphans. Also try to kill child processes before parents.

Clay

Re: zombie and/or orphan

boley janowski — Fri, 04 May 2001 21:33:26 GMT

run "top"

at the top of the screen it will report the number of zoombies on the system, you can then do a

"ps -ef | grep defunct"

this will show you which processes are just out there orphaned. If the system can not clean up these zombie processes, you will have to eventually reboot to get rid of them. Rember "top" will give you a lot of information about the way the cpu's are being worked and what processes are top users of the cpu's time. you can also type

"uptime"

this will give you load averages over a time interval its very useful for a quick glance to from the command line once you get an idea of what you system normally operates at, check it out "man uptime"

good luck

Re: zombie and/or orphan

Marty Metras — Mon, 07 May 2001 11:25:12 GMT

Thanks Boley and Clay
I found my zombie and put it to rest.

Marty

Re: zombie and/or orphan

boley janowski — Mon, 07 May 2001 11:45:50 GMT

Marty,

One last hint, when your question is answered or you figure it out, assign points or N/A and close the issue. This will help with your stats so next time you ask questions people will be more likely to answere them.

Take care