System and method for profiling energy usage of API calls that asynchronously invoke functions

A method for profiling energy usage of invoking an application programming interface (API) by an application that asynchronously invokes a callback function in a computing device, comprising:

• obtaining source code “A” for the API Ai;
• identifying each class Ci in the source code A for the API Ai that contains a callback function Di;
• modifying each class Ci by adding a callback function identifier (ID) field that is initiated to a unique value Vj upon instantiation of each object Oj that belongs to class Ci;
• identifying each location Ek in the source code A that posts the callback function Di for asynchronous execution by enqueueing object Oj instantiated from the class Ci containing the callback function Di into a callback queue;
• modifying the source code A at location Ek by adding a logging function call L to log the callback function ID Vj and current call stack into an energy profiling log;
• obtaining source code B responsible for asynchronously executing callback functions passed from the API in the callback queue;
• identifying each location F in the source code B that invokes the callback function associated with any object dequeued from the callback queue;
• modifying the source code B at the location F by calling logging functions L before and after the callback function invocation to log the callback function identifier of the dequeued object into the energy profiling log;
• executing the application thereby generating a first thread and a second thread, wherein the first thread executes a call to the API Ai that posts the callback function Di and wherein the second thread i) dequeues the callback function Di, and ii invokes the callback function Di;
• determining the caller callee relationship between the API Ai (caller) that posted Di, and the corresponding the asynchronously invoked asynchronous invocation of Dj (callee), by matching the logged callback function IDs in the energy profiling log;
• determining the energy usage of invoking the API Ai call in thread 1;
• determining the energy usage of the execution of callback function Di in thread 2;
• adding the energy usage of executing callback function Di in thread 2 to the energy usage of invoking the API Ai in thread 1;
• and
• attributing the combined energy to the API Ai invocation.