Final Review - 1最终审查.pptVIP

Advanced Topics in Software Engineering * Advanced Topics in Software Engineering * Midterm Review 4:00pm – 5:20pm, 11/10/11 Open book and notes Four problems Advanced Topics in Software Engineering * Midterm Review - 1 Overview What, why, concurrent vs sequential computation, models of concurrency (interleaving-based/true concurrency), semantics of correctness (safety liveness), unique challenges in testing and debugging Shared variables The CS problem, correctness requirements, Peterson’s algorithm, Bakery algorithm, synchronization operation, SYN-sequence, RW-sequence, version-based tracing replay Advanced Topics in Software Engineering * Midterm Review - 2 Semaphore Locks Binary semaphore, counting semaphore, lock, semaphores in Java, common patterns in semaphore-based programming, semaphore-based solutions to classical synchronization problems, fine-grained locking, PV-sequence, Lock/Unlock-sequence, permission-based tracing replay Advanced Topics in Software Engineering * Midterm Review - 3 Monitor Graphic representation, different signaling disciplines, monitor implementation, Java monitors, monitor-based solutions (dinning philosophers, bounded buffer, reader/writers), tracing/replay monitors (entry-based execution, simple and complete M-sequence) Message Passing Link/port/mailbox, synchronous vs asynchronous, rendezvous, selective wait, happened-before relation, integer/vector timestamps Homework Problems Exercises 3.5 Exercises 4.4, 4.11b., 4.18b, 4.24 Exercises 6.6 Advanced Topics in Software Engineering * Advanced Topics in Software Engineering * Simulating Counting Semaphores public final class CountingSemaphore { private int permits = 0; BinarySemaphore mutex (1); BinarySemaphore delayQ (0); public CoutingSemaphore (int initialPermits) { permits = initialPermits; } public void P () { mutex.P (); (1) -- permits; (2) if (permits 0) { (3) mutex.V (); (4) delayQ.P (); (5) } else mutex.V (); (6) } public