操作系统选择题库答案及详解_Multiple Choice Questions 5

时间:2021-09-06 03:44:03
 

Multiple Choice Questions 5

Question1

Concurrency plays a major part in which of the following specific contexts:

选择一个答案

a. Multiple applications

b. All of the above √

c. Structured applications

d. O/S structure

Question2

In order to implement mutual exclusion on a critical resource for competing processes, only one program at a time should be allowed

选择一个答案

a. In the critical section of the program √

b. None of the above

c. To Exhibit cooperation

d. To perform message passing

Question3

The following requirement must be met by any facility or capability that is to provide support for mutual exclusion:

选择一个答案

a. All of the above √

b. Only one process at a time can be allowed into a critical code section

c. A process remains in its critical code section for a finite time only

d. No assumptions can be made about relative process speeds

Question4

Processes that are designed to be able to pass execution control back and forth between themselves are referred to as

选择一个答案

a. None of the above

b. Threads

c. Coroutines √

d. Busy waiting processes

Question5

Processes that are designed to be able to pass execution control back and forth between themselves are referred to as

选择一个答案

a. Coroutines √

b. Threads

c. None of the above

d. Busy waiting processes

Question6

In a uniprocessor system, mutual exclusion can be guaranteed by

选择一个答案

a. Interleaving processes

b. Disabling interrupts √

c. Overlapping processes

d. All of the above

Question7

A semaphore that does not specify the order in which processes are removed from the queue is called a

选择一个答案

a. Binary semaphore

b. Weak semaphore √

c. None of the above

d. Strong semaphore

Question8

The finite circular buffer is used to implement which of the following basic queuing strategies

选择一个答案

a. LIFO

b. FILO

c. FIFO √

d. None of the above

Question9

A chief characteristic of a monitor is:

选择一个答案

a. A maximum of two processes may be executing in a monitor at a time

b. All of the above

c. Local data variables of the monitor are accessible by any procedure requesting use of the monitor

d. A process enters the monitor by invoking one of its procedures √

Question10

In synchronization involving message passing, the sender of a message can be

选择一个答案

a. Only blocking

b. All of the above

c. Only non-blocking

d. Either blocking or non-blocking √

Question11

In a system employing message passing, when a message is sent to a shared temporary data structure, this general approach is known as

选择一个答案

a. Direct addressing

b. Blocking

c. Indirect addressing √

d. None of the above

Question12

In a system employing message passing, the typical message is divided into two primary sections

选择一个答案

a. None of the above √

b. Body and mailbox

c. Destination ID and Source ID

d. Header and mailbox

Question13

The Reader/Writer problem requires that certain conditions be satisfied, such as:

选择一个答案

a. Any number of readers may simultaneously read from the file √

b. None of the above

c. Readers may read from the file while writers are writing to it

d. Multiple writers may write to the file simultaneouslyAny number of readers may simultaneously read from the file

Question14

A reason why the Producer/Consumer problem cannot be considered a special case of the Reader/Writer problem with a single writer (the producer) and a single reader (the consumer) is:

选择一个答案

a. None of the above

b. The Producer/Consumer problem doesnt deal with concurrency issues

c. The producer and consumer must be both reader and writer √

d. The consumer must perform writes while the reader performs reads

Question15

Examples of solutions to the concurrency problem that do not involve busy waiting are the following:

选择一个答案

a. None of the above √

b. Semaphores and monitors

c. Producers and consumers

d. Message passing and caching

Question16

A basic echo procedure (that echoes a typed character to the screen) running on a multiprocessor system can produce erroneous output if

选择一个答案

a. Two processes deadlock while in the echo code

b. Access to the echo procedure is unsynchronized √

c. None of the above

d. Access to the echo procedure is synchronized