Operating Systems Concepts Quiz 2 8e

Each active thread in a process has its own processor registers, data area, and resources.

False

Starvation is the result of a policy that liberally allocates resources.

False

The master/slave configuration is a symmetric multiprocessing system.

False

The only tangible benefit of parallel processing systems is faster processing.

False

The ____ is also called a high-level scheduler.

Job Scheduler

____ is necessary in any computer system because some resources such as memory, CPU, and dedicated devices must be exclusively allocated to one user at a time.

Mutual exclusion

____ is the policy of allowing only one process to have access to a dedicated resource.

Mutual exclusion

The two operations defined by Dijkstra to be performed on a semaphore are ____.

P and V

Fill in the missing event that causes deadlock in a database. There are two processes (P1 and P2), each of which needs to update two records (R1 and R2) and the following sequence leads to a deadlock: 1. P1 accesses R1 and locks it. 2. P2 accesses R2 and locks it. 3. ____ 4. P2 requests R1, which is locked by P1.

P1 requests R2, which is locked by P2.

The transition from ____ can be initiated by the Process Scheduler or the Job Scheduler.

RUNNING to FINISHED

The Printer Event 1 P1 requests and is allocated the printer R1. 2 P1 releases the printer R1. 3 P2 requests and is allocated the disk drive R2. 4 P2 releases the disk R2. 5 P3 requests and is allocated the plotter R3. 6 P3 releases the plotter R3. Assume that the events in the accompanying narrative take place. Which of the following statements is true?

There is no deadlock.

Each thread in a process is represented by a data structure called a ____ that contains basic information such as the thread's unique identification, state, and priority.

Thread Control Block

____ semaphores are used in the producer and consumer problem.

Three

A race introduces the element of chance, which is a highly desirable attribute, in database management.

True

Fixing a deadlock situation requires outside intervention.

True

If one job monopolizes the system, the extent of its overall effect on system performance depends on the scheduling policy and whether the job is CPU-bound or I/O-bound.

True

In Round Robin scheduling, if processing isn't finished when time expires, the job is preempted and put at the end of the READY queue and its information is saved in its Process Control Block.

True

Most computer programs alternate between CPU cycles and I/O cycles.

True

Test-and-set is a single indivisible machine instruction. In a single machine cycle, it tests to see if a key is available and, if it is, sets it to unavailable.

True

____ semaphores are used in the solution to the readers and writers problem that does not involve starvation.

Two

____ allows for faster turnaround of CPU-bound jobs.

Variable time quantum per queue

When using the WAIT and SIGNAL operations, ____ sets the process's process control block to the blocked state and links it to the queue of processes waiting to enter this particular critical region.

WAIT

An algorithm designed to detect starvation by tracking how long each job has been waiting for resources is using the concept of ____.

aging

Some systems use a strategy known as ____ to increase the priority of jobs that have been in the system for an unusually long time in order to expedite their exit.

aging

The Job Scheduler seeks to ____ when scheduling jobs.

balance CPU and I/O intensive jobs

The source code of a Java program is first compiled into an intermediate language called Java ____, which are platform-independent.

bytecodes

A computer system that can support jobs that use multiple processors to execute sets of instructions in parallel is referred to as a ____ system.

concurrent processing

A ____ of processing must be handled as a single unit.

critical region

When a compiler automatically detects instructions that can be performed in parallel, ____ is in place.

implicit parallelism

The ____ multiprocessing configuration features several complete computer systems, each with its own memory, I/O devices, CPU, and operating system.

loosely coupled

The ____ multiprocessing configuration is an asymmetric system.

master/slave

What is the name traditionally given to a semaphore that enforces the concept of mutual exclusion?

mutex

An I/O request is called a(n) ____ wait in multiprogramming environments.

natural

Failure to lock database records before updating them may result in a ____ between processes.

race

In ____ systems, deadlocks can cause critical situations.

real-time

Consider the case of a home construction company with two application programs, purchasing (P1) and sales (P2), which are active at the same time. They each need to access two files, inventory (F1) and suppliers (F2), to update daily transactions. The following series of events will cause a deadlock. Fill in the missing event in the sequence. 1. Purchasing (P1) accesses the supplier file (F2). 2. Sales (P2) accesses the inventory file (F1). 3. Purchasing (P1) doesn't release the supplier file (F2) and requests the inventory file (F1), but P1 is blocked because F1 is being held by P2. 4. Meanwhile, ____

sales (P2) doesn't release the inventory file (F1) but requests the supplier file (F2)

A problem with test-and-set is that when many processes are waiting to enter a critical region, ____ can occur because the processes gain access in an arbitrary fashion.

starvation

The first and simplest recovery method, and the most drastic, is to ____.

terminate every job that's active in the system and restart them from the beginning

The operation P in a semaphore scheme requires a(n) ____ sequence to be performed as an indivisible action in a single machine cycle.

test, fetch, decrement, and store

Deadlock can occur on a printer when ____.

the printer needs all of a job's output before it will begin printing, but the spooling system fills the available disk space with only partially completed output

In the "dining philosophers" problem, a philosopher can pick up a fork when ____.

there are two available

A(n) ____ is created by a process, and it can be scheduled and executed independently of its parent process.

thread

In its simplest form, Amdahl's Law maintains that if a given program would take one hour to run to completion with one processor, but 80 percent of the program had to run sequentially (and therefore could not be sped up by applying additional processors to it), then a resulting parallel program would run only a maximum of ____ percent faster.

20

Assume that four jobs, A-D, require the CPU cycles listed below. Using the SJN algorithm, the average turnaround time is ____. Job: A B C D CPU cycle: 5 2 6 4

9.0

____ is when each process involved in an impasse is waiting for another to voluntarily release its resources so that at least one process will be able to continue.

Circular wait

____ is a dynamic-priority preemptive scheduling algorithm built to address the critical processing requirements of real-time systems and their pressing deadlines.

Earliest Deadline First

When a job is accepted by the system, it's put on ____ and placed in a queue.

HOLD

The transition from ____ is initiated by the Job Scheduler according to some predefined policy. At this point, the availability of enough main memory and any requested devices is checked.

HOLD to READY

____ proposed a solution to the readers and writers problem that did not result in starvation for readers or writers.

Hoare

____ published a visual tool to show how deadlock conditions can be modeled using directed graphs.

Holt