In discussing Maekawa’s mutual exclusion algorithm, we gave an example of three subsets of a set of three processes that could lead to a deadlock. Use these subsets as multicast groups to show how a pairwise total ordering is not necessarily acyclic.
What will be an ideal response?
The three groups are G1 = {p1, p2}; G2 = {p2, p3}; G3 = {p1, p3}.
A pairwise total ordering could operate as follows: m1 sent to G1 is delivered at p2 before m2 sent to G2; m2 is delivered to p3 before m3 sent to G3. But m3 is delivered to p1 before m1. Therefore we have the cyclic delivery ordering m1 m2 m3 m1 We would expect from a global total order that a cycle such as this cannot occur.
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Which of the following statements is false?
a. A DirectoryStream enables a program to iterate through the contents of a directory. b. Character-based input and output can be performed with classes Scanner and Formatter. c. A relative path contains all the directories, starting with the root directory, that lead to a specific file or directory. d. Every file or directory on a disk drive has the same root directory in its path.
_____, the largest and most well-known computer network in the world, is a network of networks because it consists of a vast collection of networks that can access each other.
A. ?The Internet B. ?An extranet C. ?An intranet D. ?The World Wide Web