Linux - iotop

# iotop -o -a     

       -o, --only
             Only show processes or threads actually doing I/O, instead of showing all processes or threads. This can be  dynamically
             toggled by pressing o. 

      -a, --accumulated
             Show  accumulated  I/O instead of bandwidth. In this mode, iotop shows the amount of I/O processes have done since iotop
             started.