How to free up space, "used" by deleted file which is held by running application

1. Just kill your application

2. If you can't kill the application, you can :

a) figure out the pid of the app;
b) figure out deteled filename (lsof | grep deleted | grep pid)
c) run

# : > /proc/$app_pid/fd/$decrpiptor_corresponding_to_deleted_file