2. Consider the following program, which attempts to use semaphores for mutual exclusion. (P = sem_wait, V = sem_signal) Initially: a = 1, b = 1, c = 1. Thread 1: a. b. C. Thread 3: P(c); P(c); P(b); V(c); V(b); . P(b); V(c); P(a); P(a); V (a); V(a); V(b); For each thread, list the pairs of mutexes that it holds simultaneously. Can this program deadlock? If a < b

2. Consider the following program, which attempts to use semaphores for mutual exclusion. (P = sem_wait, V = sem_signal) Initially: a = 1, b = 1, c = 1. Thread 1: a. b. C. Thread 3: P(c); P(c); P(b); V(c); V(b); . P(b); V(c); P(a); P(a); V (a); V(a); V(b); For each thread, list the pairs of mutexes that it holds simultaneously. Can this program deadlock? If a < b

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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