ps
pstree
Visually display the parent process relationship of the child process, if the parent process is not specified, the root is init
top
'top' is a more useful command to monitor the resources used by different processes in the system. It provides real-time system status information. See http://www.cnblogs.com/vanoraxnc/p/8994589.html
w
w provides information about the currently logged in user and the processes they are executing. The display header contains information, such as the current time, the system running time, the total number of logged-in users, and the number of load balancers in the past 1, 5, and 15 minutes .
who provides a list of currently logged in users, system startup time, run level, etc.
whoami command prints current user ID
htop
htop is similar to top, but htop is an interactive text-mode process viewer. It graphically displays the CPU and memory usage and swap usage of each process through text. Use the up and down cursor keys to select a process, F7 and F8 to change the priority, and F9 to kill the process. Htop is not installed by default in the system, so additional installation is required. yum install htop
kill
This command is used to send a signal to end a process. If a process does not respond to the kill command, this may require a force kill, which is performed with the -9 parameter. Note that you must be careful when using force kill, because the process has no time to clean up the scene, and maybe the writing to the file is not complete. killall comes in handy if we don't know the process PID or if we want to kill the process by name.
kill <pid>
kill - 9 <pid> kills all processes with the same name
Reprinted from: http://www.cnblogs.com/yyjie/p/7196289.html