Operating Systems Exam 1

A job's state moves from HOLD to WAITING when it's ready to run but is waiting for the CPU. True or False?

False

A job's working set is the collection of pages that must be loaded from secondary storage. True or False?

False

A program is an active entity that requires a set of resources, including a processor and special registers, to perform its function. True or False?

False

CPU-bound jobs (such as printing a series of documents) have many brief CPU cycles and long I/O cycles. True or False?

False

Compaction should always be performed only when there are jobs waiting to get in. True or False?

False

Dual core or quad core multi-core chips are larger than a single-processor chip but produce less current leakage and heat. True or False?

False

First-come, first-served (FCFS) is a preemptive scheduling algorithm that handles jobs according to their arrival time. True or False?

False

In a demand paging scheme, the first-in first-out (FIFO) page replacement policy chooses the page least recently accessed to be swapped out. True or False?

False

The Memory Manager, the Interface Manager, the User Manager, and the File Manager are the four essential managers of every major operating system. True or False?

False

The Processor Manager is a composite of at least two submanagers: one in charge of job scheduling and the other in charge of program scheduling. True or False?

False

The content of a random access memory (RAM) chip is nonvolatile, meaning that it is not erased when the power is turned off. True or False?

False

The control program that handles the interruption sequence of events is called the event scheduler. True or False?

False

The first-fit algorithm assumes that the Memory Manager keeps only one list containing free memory blocks. True or False?

False

The key to the successful implementation of demand paging is the use of a high-speed CPU. True or False?

False

When using priority scheduling, priorities are assigned to jobs by the owner of the job (the user). True or False?

False

In a paged memory allocation scheme, a simple ____ has one entry for each page frame that shows its location and its free/busy status. a. Memory Map Table b. Memory Management Table c. Page Access Table d. Job Table

Memory Map Table

1. Networking was not always an integral part of operating systems. True or False?

True

A single processor can be shared by several jobs, or several processes, but only if the operating system has a scheduling policy, as well as a scheduling algorithm, to determine when to stop working on one job and proceed to another. True or False?

True

After relocation and compaction, both the free list and the busy list are updated. True or False?

True

An important function of the Processor Manager is to keep track of the status of each job, process, and thread. True or False?

True

As a process moves through the system, its status changes. Possible process statuses include HOLD, READY, RUNNING, WAITING, and FINISHED. True or False?

True

Associative memory is a name given to several hardware registers that are allocated to each active job whose task is to associate segment and page numbers belonging to the job being processed with their main memory addresses. True or False?

True

Context switching is required by all preemptive algorithms. True or False?

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 or False?

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 or False?

True

In a dynamic partition system, a null entry in the busy list occurs when a memory block between two other busy memory blocks is returned to the free list. True or False?

True

In the relocatable dynamic partitions scheme, the Memory Manager relocates programs to gather together all of the empty blocks and compact them to make one block of memory large enough to accommodate some or all of the jobs waiting to get in. True or False?

True

It is possible to minimize response time by running only interactive jobs and letting batch jobs wait until the interactive load ceases. True or False?

True

Memory defragmentation is performed by the operating system to reclaim fragmented space. True or False?

True

Most computer programs alternate between CPU cycles and I/O cycles. True or False?

True

Research continues to focus on finding the optimum allocation scheme. True or False?

True

The Device Manager is responsible for connecting with every device that's available on the system and for choosing the most efficient way to allocate them. True or False?

True

The Job Table (JT) contains two values for each active job: the size of the job and the memory location where its Page Map Table is stored. True or False?

True

The Memory Manager is in charge of main memory, widely known as ROM. True or False?

True

The algorithm used to store jobs into memory in a fixed partition system requires a few more steps than the one used for a single-user system because the size of the job must be matched with the size of the partition to make sure it fits completely. True or False?

True

The bounds register is used to store the highest (or lowest, depending on the specific system) location in memory accessible by each program. True or False?

True

The fixed partition scheme works well if all of the jobs run on the system are of the same size or if the sizes are known ahead of time and don't vary between reconfigurations. True or False?

True

The operating system manages each and every piece of hardware and software. True or False?

True

The primary advantage of storing programs in noncontiguous page frames (in a paged memory allocation scheme) is that main memory is used more efficiently because an empty page frame can be used by any page of any job. True or False?

True

The shortest remaining time (SRT) algorithm is not recommended for interactive systems. True or False?

True

Virtual memory can be implemented with both paging and segmentation. True or False?

True

Web browsers use multithreading routinely. For example, one thread can retrieve images while another sends and retrieves e-mail. True or False?

True

When using a multiple-level queue strategy, aging is used to ensure that jobs in lower-level queues will eventually complete their execution. True or False?

True

A ____ chip holds software that is used to start the computer. a. ROM b. CPU c. RAM d. buffer

a. ROM

The goal of the ____ memory allocation algorithm is to find the smallest memory block into which a job will fit. a. best-fit b. smallest-fit c. first-fit d. dynamic-fit

a. best-fit

A disadvantage of segmented memory allocation is ____. a. external fragmentation b. internal fragmentation c. the physical size requirements of main memory d. the number of page faults

a. external fragmentation

A(n) ____ in the busy list occurs when a memory block between two other busy memory blocks is returned to the free list. a. null entry b. joined entry c. blank line d. empty entry

a. null entry

In a single -user system, jobs are processed ____. a. sequentially b. intermittently c. randomly d. in order of longest job to shortest job

a. sequentially

In demand paging, when an excessive number of pages are moved back and forth between main memory and secondary storage, it is called ____. a. thrashing b. swapping c. faulting d. paging

a. thrashing

In demand paging, the collection of pages residing in memory that can be accessed directly without incurring a page fault is called the ____. a. working set b. page set c. denning set d. job set

a. working set

Assume that four page frames are available and are numbered 1-4. Pages A-D have been loaded into page frames 1-4 in order. The program has accessed the pages in the following order: B, D, A, C. Assume that page E is requested. The ____ page frame will be loaded when the LRU algorithm is used. a. 1 (Page A) b. 2 (Page B) c. 3 (Page C) d. 4 (Page D)

b. 2 (Page B)

____ can be thought of as being an intermediary between main memory and the special-purpose registers, which are the domain of the CPU. a. Paging b. Cache memory c. Virtual memory d. Segmenting

b. Cache memory

____ is the practice of using Internet-connected resources to perform processing, storage, or other operations. a. Process management b. Cloud computing c. Command line interfacing d. Network management

b. Cloud computing

____ of memory is performed by the operating system to reclaim fragmented sections of the memory space. a. Redirection b. Compaction c. Deallocation d. Reallocation

b. Compaction

The ____ is often very different from one operating system to the next, sometimes even between different versions of the same operating system. a. File Manager b. User Interface c. Process Manager d. Memory Manager

b. User Interface

The name for the core portion of an operating system is the ____. a. manager b. kernel c. nucleus d. center

b. kernel

In the fixed-partition memory management scheme, the table that the Memory Manager uses to keep track of jobs is composed of the ____. a. partition size, status, and access b. partition size, memory address, access, and status c. partition size, memory address, and status d. status, access, and memory address

b. partition size, memory address, access, and status

With segmented memory allocation, each job is divided into several ____ of different sizes, one for each module that contains pieces that perform related functions. a. modules b. segments c. pages d. partitions

b. segments

Consider the following page fault handler algorithm. Replace the * in the algorithm with ____. 1 If there is no free page frame Then select page to be swapped out using page removal algorithm update job's Page Map Table If content of page had been changed then * End if End if 2 Use page number from step 3 from the Hardware Instruction Processing Algorithm to get disk address where the requested page is stored 3 Read page into memory 4 Update job's Page Map Table 5 Update Memory Map Table 6 Restart interrupted instruction a. save page to main memory b. write page to disk c. mark page as being changed in PMT d. choose another page

b. write page to disk

The cache hit ratio is ____, if the total number of requests is 10 and 6 of those are found in cache memory. a. 6% b. 10% c. 60% d. 100%

c. 60%

If a particular demand paging configuration has 9 page interrupts out of 11 page requests, failure rate is ____. a. 18% b. 52% c. 82% d. 95%

c. 82%

The word ____ is used to indicate that a program is permanently held in ROM (read only memory), as opposed to being held in secondary storage. a. software b. shareware c. firmware d. hardware

c. firmware

The ____ method keeps the free/busy lists organized by memory locations, from low-order memory to high-order memory. a. fixed partition allocation b. dynamic fit memory allocation c. first-fit memory allocation d. best-fit memory allocation

c. first-fit memory allocation

There are two types of real-time systems depending on the consequences of missing the deadline. A ____ real-time system risks total system failure if the predicted time deadline is missed. a. constrained b. soft c. hard d. restricted

c. hard

By compacting and relocating, the Memory Manager optimizes the use of memory and thus improves throughput. However, it also requires more ____ than the other memory allocation schemes discussed in this chapter. a. null entries b. segmentation c. overhead d. main memory

c. overhead

In a relocatable dynamic partition scheme, the ____ contains a value that must be added to each address referenced in a program so that the system will be able to access the correct memory addresses after relocation. a. load register b. compaction register c. relocation register d. bounds register

c. relocation register

When there is an excessive amount of page swapping between main memory and secondary storage, the operation becomes inefficient, which is called ____. a. excessive demand paging b. hot swapping c. thrashing d. overswapping

c. thrashing

The efficiency of a batch system is measured in ____, which is the number of jobs completed in a given amount of time. a. processes b. turnaround time c. throughput d. threads

c. throughput

A system with ____ divides programs into parts and keep them in secondary storage, bringing each part into memory only as it is needed. a. passive multiprogramming b. segmented processing c. virtual memory d. shared memory

c. virtual memory

Assume that four jobs, A-D, arrived at the same time and require the CPU cycles listed below. Using the SJN algorithm, the average turnaround time is ____. Job: ABCD CPU Cycle: 5 3 6 4 a. 5.5 b. 6.8 c. 9.0 d. 10.0

d. 10.0

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 2 2 3 Job: A B C D CPU Cycle: 6 2 1 5 a. 2.5 b. 6.25 c. 7.75 d. 6

d. 6

Consider the following four cases. The LRU policy,____, will be least likely to swap. a. Case 1: Not modified AND not referenced b. Case 2: Not modified BUT was referenced c. Case 3: Was modified BUT was not referenced d. Case 4: Was modified AND referenced

d. Case 4: Was modified AND referenced

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: ABCD CPU Cycle: 5 2 6 1 a. A b. B c. C d. D

d. D

The ____ uniquely identifies each resource, starts its operation, monitors its progress, and, finally, deallocates it, making the operating system available to the next waiting process. a. Keyboard Manager b. File Manager c. Memory Manager d. Device Manager

d. Device Manager

____ systems are used in time-critical environments where reliability is key and data must be processed within a strict time limit. a. Hybrid b. Interactive c. Embedded d. Real-time

d. Real-time

A hybrid system is a combination of the ____ systems. a. interactive and real-time b. batch and real-time c. real-time and general-purpose d. batch and interactive

d. batch and interactive

In a relocatable dynamic partition scheme, the ____ ensures that, during execution, a program won't try to access memory locations that don't belong to it. a. relocation register b. load register c. compaction register d. bounds register

d. bounds register

The phenomenon of less-than-complete use of memory space in a fixed partition is called ____. a. dynamic fragmentation b. fixed fragmentation c. external fragmentation d. internal fragmentation

d. internal fragmentation

The most common mechanism for implementing multiprogramming was the introduction of the ____ concept, whereby the CPU was notified of events needing operating systems services. a. sharing b. paging c. messaging d. interrupt

d. interrupt

The primary advantage of storing programs in noncontiguous locations is that ____. a. every program will be able to run b. secondary storage is accessed more quickly c. multiple programs can run at the same time d. main memory is used more efficiently

d. main memory is used more efficiently

With the development of ____ technology, a single chip was equipped with two or more processor cores. a. networking b. multiprogramming c. multimedia d. multicore

d. multicore