You can use the utility “iotop” to find out the “disk usage of each process” running on your system.
Type this command at terminal to install “iotop” on your system.
$ sudo apt-get install iotop
If you just want to know the cpu usage and memory usage of each process, then simply use “top” command for it.
“iotop” is also same as “top“, but it shows disk usage of all processes and threads.