Cloud Computing Theory and Practice chapter 2 problem 2 Given a system of four concurrent threads t1,t2,t3 and t4 we take a snapshot of the consistent state of the system after 3, 2, 4, and 3 events in each thread, respectively; all but the second event in each thread are local events. The only communication event in thread t1 is to send a message to t4 and the only communication event in thread t3 is to send a message to t2. Draw a space-time diagram showing the consistent cut; mark individual events on thread ti as eji . How many messages are exchanged to obtain the snapshot in this case? The snapshot protocol allows the application developers to create a checkpoint. An examination of the checkpoint data shows that an error has occurred and it is decided to trace the execution. How many potential execution paths must be examined to debug the system