Suppose we are dealing with a set of 4 processes P = {P1, P2, P3, P4} that are expressed by the following precedence relation: ⇒: {(P3, P4), (P1, P2), (P2, P4)} Show how you can use semaphores to enforce these constraints (i.e. the precedence relation ⇒). Recall that semaphores have two operations, P() and V() which decrement and increment the semaphore respectively. Also recall that semaphores can put the process to sleep under certain circumstances (which I hope that you remember). Note: This means showing when the P and V operations will be called on each semaphore (for any process which uses them).

Suppose we are dealing with a set of 4 processes P = {P1, P2, P3, P4} that are expressed by the following precedence relation: ⇒: {(P3, P4), (P1, P2), (P2, P4)} Show how you can use semaphores to enforce these constraints (i.e. the precedence relation ⇒). Recall that semaphores have two operations, P() and V() which decrement and increment the semaphore respectively. Also recall that semaphores can put the process to sleep under certain circumstances (which I hope that you remember). Note: This means showing when the P and V operations will be called on each semaphore (for any process which uses them).

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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