Study Guide #2 Pt. 2

DATA

In general, parallel systems can be put into two broad categories: ____ level parallelism and instruction level parallelism. a. resource c. data b. register d. task

20

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. a. 5 c. 20 b. 10 d. 25

there are two available

In the "dining philosophers" problem, a philosopher can pick up a fork when ____. a. there is one available b. there are two available c. no other philosopher is eating d. it is his/her turn, going in numerical order from one philosopher to the next

Machine Cycle

Lock and key synchronization must take place within a single ____. a. instruction c. processor b. computer d. machine cycle

Lightweight Processes

Most current operating systems support the implementation of threads, or ____, which have become part of numerous application packages. a. parallel processes c. heavyweight processes b. lightweight processes d. semaphores

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. a. lagging c. bumping b. aging d. accelerated priority

Avoidance

The Banker's Algorithm is an example of a (n) ____ policy. a. mutual exclusion c. avoidance b. detection d. recovery

Thread

The Java ____ class is a collection of methods used to start, run, stop, and check the status of a thread. a. Thread c. Distributed b. Multiprocessing d. Concurrency

Balance CPU and I/O Intensive jobs.

The Job Scheduler seeks to ____ when scheduling jobs. a. run all CPU intensive jobs first c. balance CPU and I/O intensive jobs b. run all I/O intensive jobs first d. run the quickest jobs first

There is no deadlock

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? a. There is no deadlock. c. Event 5 caused deadlock. b. Event 4 caused deadlock. d. Event 6 caused deadlock.

Job Scheduler

The ____ is also called a high-level scheduler. a. Process Scheduler c. Program Scheduler b. Job Scheduler d. Thread Scheduler

Loosely coupled

The ____ multiprocessing configuration features several complete computer systems, each with its own memory, I/O devices, CPU, and operating system. a. loosely coupled c. symmetric b. master/slave d. synchronized

Master/Slave

The ____ multiprocessing configuration is an asymmetric system. a. loosely coupled c. start/end b. master processors d. master/slave

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

The first and simplest recovery method, and the most drastic, is to ____. a. select a non-deadlocked job, preempt the resources it's holding, and allocate them to a deadlocked process so it can resume execution, thus breaking the deadlock b. identify which jobs are involved in the deadlock and terminate them one at a time, checking to see if the deadlock is eliminated after each removal c. terminate only the jobs involved in the deadlock and ask their users to resubmit them d. terminate every job that's active in the system and restart them from the beginning

Batch

The first-come, first-served (FCFS) algorithm is fine for most ____ systems. a. multiuser c. Interactive b. user initiated d. Batch

test, fetch, decrement, and store

The operation P in a semaphore scheme requires a (n) ____ sequence to be performed as an indivisible action in a single machine cycle. a. test, fetch, increment, and store c. increment and store b. test, fetch, decrement, and store d. decrement and store

hierarchal ordering

The scheme of ____ removes the possibility of a circular wait and therefore guarantees the removal of deadlocks. a. hierarchical ordering c. saving and restoring job state b. preemption d. requesting all resources before job run

Bytecodes

The source code of a Java program is first compiled into an intermediate language called Java ____, which are platform-independent. a. beans c. bits b. nibs d. bytecodes

RUNNING to Finished

The transition from ____ can be initiated by the Process Scheduler or the Job Scheduler. a. WAITING to READY c. RUNNING to FINISHED b. RUNNING to WAITING d. HOLD to READY

HOLD to READY

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. a. READY to RUNNING c. RUNNING back to READY b. RUNNING to WAITING d. HOLD to READY

Implicit parallelism

When a compiler automatically detects instructions that can be performed in parallel, ____ is in place. a. automatic parallelism c. explicit parallelism b. array parallelism d. implicit parallelism

the type of interrupt is described and stored

When the operating system detects a non-recoverable error, the following step is performed first by the interrupt handler: ____. a. the state of the interrupted process is saved b. the type of interrupt is described and stored c. the interrupt is processed d. the processor resumes operation

WAIT

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. a. TS c. WAIT b. SIGNAL d. BLOCK

Find a process that is currently using a resource and not waiting for one.

Which of the following is the first step in reducing a directed graph to eliminate deadlock? a. Remove the process that is holding on to the most resources. b. Find a process that's waiting only for resource classes that aren't fully allocated c. Find a process that is currently using a resource and not waiting for one. d. Find the oldest process and remove it from the graph.

Variable time quantum per queue

____ allows for faster turnaround of CPU-bound jobs. a. No movement between queues c. Variable time quantum per queue b. Movement between queues d. Aging

Dijkstra

____ developed the Banker's Algorithm. a. Havender c. Dijkstra b. Holt d. Lane & Mooney

Earliest Deadline First

____ is a dynamic-priority preemptive scheduling algorithm built to address the critical processing requirements of real-time systems and their pressing deadlines. a. Variable Time Quantum Per Queue c. Shortest Job Next b. Round Robin d. Earliest Deadline First

Mutual Exclusion

____ is the policy of allowing only one process to have access to a dedicated resource. a. No preemption c. Resource holding b. Circular wait d. Mutual exclusion

Circular Wait

____ 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. a. Mutual exclusion c. Circular wait b. Resource holding d. No preemption

Spooling

____ is when, in modern printing systems, a disk accepts output from several users and acts as a temporary storage area for all output until the printer is ready to accept it. a. Phishing c. Spooling b. Lagging d. Spoofing

Hoare

____ proposed a solution to the readers and writers problem that did not result in starvation for readers or writers. a. Hoare c. Heymans b. Courtois d. Parnas

Holt

____ published a visual tool to show how deadlock conditions can be modeled using directed graphs. a. Havender c. Dijkstra b. Holt d. Lane & Mooney

Multiprogramming

____ requires that the processor be allocated to each job or to each process for a period of time and de-allocated at an appropriate moment. a. Cyclic programming c. Multiprogramming b. Dedicated processing d. Multi-core processing

Three

____ semaphores are used in the producer and consumer problem. a. One c. Three b. Two d. Four

Two

____ semaphores are used in the solution to the readers and writers problem that does not involve starvation. a. Zero c. Two b. One d. Three

Mutual Exclusion

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. a. Mutual exclusion c. No preemption b. Resource holding d. Circular wait

Thread

A (n) ____ is created by a process, and it can be scheduled and executed independently of its parent process. a. thread c. Mini-process b. program d. instruction set

Critical Region

A ____ of processing must be handled as a single unit. a. line c. critical region b. segment d. semaphore

Concurrent Processing

A computer system that can support jobs that use multiple processors to execute sets of instructions in parallel is referred to as a ____ system. a. concurrent processing c. parallel extraction b. process synchronization d. processing optimization

80

A general rule of thumb for selecting a proper time quantum in Round Robin scheduling is that it should be long enough to allow ____ percent of the CPU cycles to run to completion. a. 20 c. 80 b. 60 d. 100

Natural

An I/O request is called a (n) ____ wait in multiprogramming environments. a. forced c. scheduled b. natural d. indirect

Aging

An algorithm designed to detect starvation by tracking how long each job has been waiting for resources is using the concept of ____. a. deadlock c. preemption b. aging d. round robin

B

Assume that four jobs, A-D, are in the READY queue at Time 0 and require the CPU cycles listed below. Using the SJN algorithm, the ____ job is run first. Job: A B C D CPU cycle: 5 2 6 4 a. A c. C b. B d. D

9.0

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 a. 5.5 c. 9.0 b. 6.8 d. 11.1

6.25

Assume that jobs A-D arrive in the READY queue in quick succession and have the CPU cycle requirements listed below. Using the SRT algorithm, the average turnaround time is ____. Arrival time: 0 1 2 3 Job: A B C D CPU cycle: 6 3 1 4 a. 2.5 c. 7.75 b. 6.25 d. 9.0

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

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, ____ a. sales (P2) doesn't release the inventory file (F1) but requests the supplier file (F2) b. sales (P2) does release the inventory file (F1) and then requests the supplier file (F2) c. purchasing (P1) does release the supplier file (F2) which is then requested by sales (P2) d. purchasing (P1) exits

Thread Control Block

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. a. Thread Control Block c. Thread Pointer b. Thread State Block d. Thread Queue

While the control unit is moving the arm to cylinder 20, P1 is put on hold and the I/O channel is free to process the next I/O request.

Fill in the missing event that causes livelock. At an insurance company, the system performs many daily transactions. One day, the following series of events ties up the system: 1. Process P1 wishes to show a payment, so it issues a command to read the balance, which is stored in cylinder 20 of a disk pack. 2. ____ 3. P2 gains control of the I/O channel and issues a command to write someone else's payment to a record stored in cylinder 310. If the command is not "locked out," P2 will be put on hold while the control unit moves the arm to cylinder 310. 4. Because P2 is "on hold," the channel is free to be captured again by P1, which reconfirms its command to "read from cylinder 20." 5. Since the last command from P2 had forced the arm mechanism to cylinder 310, the disk control unit begins to reposition the arm to cylinder 20 to satisfy P1. The I/O channel would be released because P1 is once again put on hold, so it could be captured by P2, which issues a WRITE command only to discover that the arm mechanism needs to be repositioned. a. While the control unit is moving the arm to cylinder 20, P1 is put on hold and the I/O channel is free to process the next I/O request. b. P1 discovers that another process has locked the portion of the disk it needs to access. c. P2 is put on hold while the control unit moves the arm to satisfy P1's request d. P1 is unable to find the information it needs, so requests a different READ operation for a different cylinder.

P2 requests drive 2 and gets it.

Fill in the missing step in the following deadlock situation. Two users from the local board of education are each running a program (P1 and P2), and both programs will eventually need two DVD drives to copy files from one disc to another. Only two DVD-R drives are available and they're allocated on an "as requested" basis. Soon the following sequence transpires: 1. P1 requests drive 1 and gets it. 2. ____ 3. P1 requests drive 2 but is blocked. 4. P2 requests drive 1 but is blocked. a. P1 requests drive 2. c. P2 requests drive 1 but is blocked. b. P2 requests drive 2 and gets it. d. P1 releases drive 1.

real-time

In ____ systems, deadlocks can cause critical situations. a. batch c. real-time b. interactive d. general purpose