Ever wondered which application right now is writing to the hard drive. Currenlty trying to minimize the hard drive usage on my laptop and tried to answer this exact question.

Unfortunately I did not find a tool to exactly tell me which application is currently writing to which file on the harddrive. But a least with the tool iotop I was able to find out, which application is writing to the hard disc at all. Under ubunto or debian install this simply by invoking

apt-get install iotop

Like top this python-application continuously outputs the current processes which are using the hard drive. But you have to be very attentive to catch all applications while this tool is running. To get a better overview of all hard drive activity call the tool with the following parameters:

sudo iotop -qqqtaPob

This parameters put iotop into a mode where it outputs something like a logfile to the screen. Just let this run in the background, do something on your computer and then check, what tools where using the harddrive. Take a look in the man-pages of iotop to get the meaning of the parameters.

Now I am looking for a tool to really see to which files a running process currently is writing to. Some tests with strace -f -e trace=file -p PID where promising but failed if the running process opens the file only once at startup.

Anyone any ideas how to really see what and where a process writes something to the hard drive?