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Problem killing process

I'm having a bit of trouble killing a process. I was using rpm to remove a package when the terminal windo froze. So I opened up a new terminal and tried to kill the rpm process but with no luck.

Anyone any ideas?

Thanks
Paddy

Code:

[root@paddy ~]# ps -A | grep rpm

32258 pts/1    00:00:00 rpm

[root@paddy ~]# kill -9 32258

[root@paddy ~]# ps -A | grep rpm

32258 ?        00:00:00 rpm

[root@paddy ~]# kill -15 32258

[root@paddy ~]# ps -A | grep rpm

32258 ?        00:00:00 rpm

[root@paddy ~]# kill -9 32258

[root@paddy ~]# ps -A | grep rpm

32258 ?        00:00:00 rpm

See what state the process is in with "ps aux ". If it's stuck in uninterruptable sleep (state D) it can't be killed, even with kill -9. I've seen this happen with corrupt RPM databases.

Thanks for the info, I actually ended up rebooting my machine because I wasn't able to kill the process!

Paddy

It is better to use kill code 15 before using kill code 9 to force the program to quit. Kill code 15 means terminate, so it is the same as hitting CTRL+C. Sending kill code 9 to a program sometimes turns it into a zombie. A zombie process will not take up resources but a reboot is the only way to get rid of it.

Some processes, you will have to terminate or kill its parent PID.

Thanks I'll remember that for next time. It's annoying when a program like rpm or yum gets zombied like this because it locks some files and the only thing I can do is reboot before I can use that program again.

Paddy

Quote:

Originally Posted by paddyjoy

Zombies happen when a parent forks a child process and the child dies. The child becomes a zombie until either (1) the parent executes a wait() command on the child, or (2) the parent dies. The "parent executes a wait()" scenerio is where the somewhat morbid recommendation that "Parents should reap their dead children" comes from. The next time you zombie a process and can't seem to get rid of it, try logging off and back on again. That may kill the parent, thus freeing the zombie without a reboot. I'm not really familiar with the workings of rpm (I use Debain and dpkg/apt-get), but you can see after your first kill attempt at rpm that it looses it's controlling TTY (was "pts/1" before the kill, then "?" after the kill). I always that zombies showed up in a ps listing as "<defunct>". That's the way it's been for years on many different Unix systems I've worked with. Don't know specifically about Linux though. I haven't been using Linux all that long and haven't looked closely.

Thanks I'm going to try and reproduce it again so that I can test out the different methods of resolving it. After the first kill attempt wasn't successful I killed/closed the terminal window that had frozen, thats when the pts/1 changed to ? I was hoping at the time that killing the parent would also kill the child rpm process. It usually does but maybe this was just a freak occurence!

Paddy