MacOS – Blank process name in Activity Monitor on OS X Mavericks

According to wikipedia, a zombie process is a process that has completed executing, but still has an entry in the process table. In other words, a zombie process has finished executing, but it hasn't been cleaned up yet.

When a process finishes, its return code needs to be returned to the parent process. Normally, this happens immediately, so you don't see the zombie process. However, sometimes, the parent process doesn't cooperate, and the zombie stays in the process table indefinitely.

If you want to get rid of a zombie process, you have three options:

1. Wait. Hopefully it'll clear up on its own.
2. Send a SIGCHLD to the zombie's parent. If it's behaving correctly, it'll fetch the return code of the zombie process, and the system can then reap the zombie process.
3. Kill the parent process. When you kill a process, its children are adopted by init, which will clean everything up for you.

It seems that this feature – since Apple has changed the way how they display memory usage – isn't a option anymore:

This is no longer an option, especially since Mavericks has new memory management routines (ie, memory compression) that make the charting of memory usage less straightforward. Apple has switched to a new "Memory Pressure" approach to viewing memory usage, which is available in the Memory section of Activity Monitor, but so far has not been added as a Dock icon option. Hopefully Apple will do so, as this would perhaps be one of the more useful Dock icon options.

I've got that from here one would hope that at some point we could graph memory pressure in the dock using Apple's Activity monitor as opposed to needing to open the whole tool with a window that shows many other items.