How to Kill Zombie Processes in Ubuntu 18.04 LTS

You can kill the zombie processes through the following ways: Through the Graphical User Interface.
...
Through the GUI

1. Open the System Monitor utility through Ubuntu Dash.
2. Search for the term Zombie through the Search button.
3. Select the zombie process, right-click and then select Kill from the menu.

1. How do I kill a zombie process in Linux?
2. How do I clean up zombie processes?
3. How zombie processes are terminated?
4. How do I kill a process in Ubuntu?
5. How do you kill a process?
6. How do you identify a zombie?
7. How do I fix zombie processes?
8. What causes a zombie process?
9. How can we stop zombie processes?
10. Is it bad to have zombie processes on your system?
11. What is zombie state?
12. What is Zombie thread?

How do I kill a zombie process in Linux?

You can follow below steps to attempt killing zombie processes without system reboot.

1. Identify the zombie processes. top -b1 -n1 | grep Z. ...
2. Find the parent of zombie processes. ...
3. Send SIGCHLD signal to the parent process. ...
4. Identify if the zombie processes have been killed. ...
5. Kill the parent process.

How do I clean up zombie processes?

A zombie is already dead, so you cannot kill it. To clean up a zombie, it must be waited on by its parent, so killing the parent should work to eliminate the zombie. (After the parent dies, the zombie will be inherited by pid 1, which will wait on it and clear its entry in the process table.)

How zombie processes are terminated?

The zombie processes can be removed from the system by sending the SIGCHLD signal to the parent, using the kill command. If the zombie process is still not eliminated from the process table by the parent process, then the parent process is terminated if that is acceptable.

How do I kill a process in Ubuntu?

How Do I End a Process?

1. First select the process that you want to end.
2. Click on the End Process button. You will get a confirmation alert. Click on “End Process” button to confirm that you want to kill the process.
3. This is the simplest way way to stop (end) a process.

How do you kill a process?

1. What Processes Can You Kill in Linux?
2. Step 1: View Running Linux Processes.
3. Step 2: Locate the Process to Kill. Locate a Process with ps Command. Finding the PID with pgrep or pidof.
4. Step 3: Use Kill Command Options to Terminate a Process. killall Command. pkill Command. ...
5. Key Takeaways on Terminating a Linux Process.

How do you identify a zombie?

Types of Zombies and How to Identify them

1. Check out the pale, bloodless appearance to help identify a zombie. Zombies also appear in torn, musty clothing that barely covers their decaying flesh. ...
2. Look for zombies if you're near a cemetery or morgue. ...
3. Identify staggering movements. ...
4. Smell the decomposing flesh.

How do I fix zombie processes?

The only reliable solution is to kill the parent process. When it's terminated, its child processes are inherited by the init process, which is the first process to run in a Linux system (its process ID is 1).

What causes a zombie process?

Zombie processes are when a parent starts a child process and the child process ends, but the parent doesn't pick up the child's exit code. The process object has to stay around until this happens - it consumes no resources and is dead, but it still exists - hence, 'zombie'.

How can we stop zombie processes?

Different ways in which the creation of Zombie can be Prevented. 1. Using wait() system call : When the parent process calls wait(), after the creation of a child, it indicates that, it will wait for the child to complete and it will reap the exit status of the child.

Is it bad to have zombie processes on your system?

Dangers of Zombie Processes

Zombie processes don't use up any system resources. (Actually, each one uses a very tiny amount of system memory to store its process descriptor.) ... However, a few zombie processes hanging around are no problem – although they do indicate a bug with their parent process on your system.

What is zombie state?

On Unix and Unix-like computer operating systems, a zombie process or defunct process is a process that has completed execution (via the exit system call) but still has an entry in the process table: it is a process in the "Terminated state".

What is Zombie thread?

A zombie thread is a joinable thread which has terminated, but which hasn't been joined. Normally, either a thread should be joined at some time, or it should be detached. Otherwise, the OS maintains its state for some possible future join, which takes resources.