Low performance of HP Unix 11i machine

[contactvenky2005]

When i run top command and check the performance of an unix machine, i am able to find 14 zombies processes running. Will it be the reason for slow performance of my machine?. If so, Suggest me how to kill the zombie processes.

[Torsten.]

You cannot kill a zombie - it is already dead.

The only solution is a reboot.

[RAC_1]

That might be or might not be the reason for performance problem. You can not kill zombies. They are like dead processes, waiting on some i/os.

With glance, do you see any of the resources hitting maximum-cpu, disk, memory etc?

[James R. Ferguson]

Hi:

As noted, you can't kill a 'zombie' process. As the name implies, it's already dead!

Zombies arise when a parent process fails to ignore its child's termination or fails to wait on its child.

Zombie processes consume a slot in the kernel's process table (whose limits are governed by the kernel tunable, 'nproc') but otherwise do no harm. They don't consume memory nor processor cyclces. At worst, you waste potential slots in the process table for allocating new processes.

Regards!

...JRF...

[Bill Hassell]

zombies or defunct processes are the result of imporper handling of parent-child programs. Byt the 14 zombies have no effect on performance. You need to identify why you think it is slow. For instance, did the system run faster in the past? Or is the system being compared to another system? Performance problems require an understanding of what is normal for the application programs in terms of disk I/O, LAN, memory and CPU usage.

[Steven E. Protter]

Shalom,

Zombies aren't really doing anything.

First you try a kill

If that fails kill -9

If that fails only a system boot will fix them.

You clearly have an application problem and need to track the processes back to the application and deal with the vendor or programmers involved.

SEP

[contactvenky2005]

thankx a lot. The replies were really helpful to me. As it was sugested there was no problem with zombie process, ather it was with i/o from disk