profiling middleware

Performance tuning is a big topic. The current profiling method monitor the cluster and provide system and process level statistics information which can tell how well the system is running. But it doesn't provide more details about code level information and explain why. This proposal can give us deeper analysis into the code and tell what happened in the background and explain why. For example:
1)How often the function in specific module is called?
2)How long it take to execute these calls?
3)Where's the most time consumed?
4)Why does the response time of container PUT operation increase?
5)Where does the memory leaking happen? how much memory consumed by specific code snippet?