View disk usage
df -h
View CPU, memory usage
top
The first column of PID is the process number. If you need to view the detailed information of the process corresponding to the specified process number, you can use the command:
ps -ef|grep Process ID
Such as: ps -ef|grep 5533
More instructions on the top command: http://huangqiqing123.iteye.com/blog/2391345
View the size of the specified file and folder
http://huangqiqing123.iteye.com/blog/2192851