Can't stop MongoDB process on CentOS
do a command like this

ps -ef | grep "MONGO" 


You will see output like 

502  8066     1   0 12:23pm ??        12:25.00  /Applications/PyCharm.app/Contents/MONGO/pycharm


Now before you do the next command understand that killing a process when it may or may not be doing something is a VERY VERY DANGEROUS habit.

So if this corrupts your MongoDB Database - it is because you did this command.....

kill -9 8066  


8066 is the 2nd number you can see from the ps command.

You can tell if the process is consuming cpu/disk using other systems tools such as 


top
sar
instat


If these processes look like the MongoDB Process is doing some work - then the chances of something bad usually increases.

Good Luck !!

Thought: Ask the server to restart ??