Any app or script to track per process usage?
You could also use a shell command like this:

while :;do ps -p 1234 -o %cpu=;sleep 1;done


Replace 1234 with the pid of the process.

You can use gnuplot to create a graph for the data:

gnuplot&lt;&lt;&lt;'set term png;set output "/tmp/plot.png";plot "/tmp/data" with boxes'
qlmanage -p /tmp/plot.png