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Politecnico di Milano FACOLTÀ DI INGEGNERIA DELL ’INFORMAZIONE Advanced Operating Systems A.A. 2015-2016 – Exam date: 18 December 2015 Prof. William FORNACIARI Surname (readable)........................................ Name (readable)............................ Matr................................................................. Signature........................................ Q1 Q2 Q3 TOT NOTES It is forbidden to refer to texts or notes of any kind as well as interact with their neighbors. Anyone found in possession of documents relating to the course, although not directly relevant to the subject of the examination will cancel the test. It is not allowed to leave during the first half hour, the task must still be returned, even if it is withdrawn. The presence of the writing (not delivered) implies the renunciation of any previous ratings. Question Q1 Describe the general characteristics of a scheduling for real-time, possibly including a comparison between Rate Monotonic and EDF. 1/6 2/6 Question Q2 A C++ module is composed of two files: priorityexecutor.h and priorityexecutor.cpp. These two files contain a single C++ class, named PriorityExecutor that must have at least the following public interface: class PriorityExecutor { public: PriorityExecutor(); void execute(std::function<void ()> task, bool highPriority); ~PriorityExecutor(); }; This class should contain a thread that executes the tasks passed to it through the execute() member function. Tasks have two priority levels, high and low. The tasks must not be executed directly in the execute() member function, but rather passed to the background thread. The background thread should execute each task in a run-to-completion fashion, and when it has finished running a task, should both high and low priority…