10. The device according to claim 9 , wherein the clustering handler further comprises: a hotspot generator for recognizing significant code clusters from the result of computer system performance according to a predetermined metric to generate a sorted list of the hotspots.
11. The device according to claim 10 , wherein the predetermined metric is tick percentage, and wherein the tick percentage is the rate of the ticks of a respective code cluster to sum of the ticks, and the ticks are the executing times of the respective code cluster counted by a counter.