Understanding Operating System CH 6

critical region

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

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.

starvation

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.

False

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

True

Early programming languages did not support the creation of threads or the existence of concurrent processes. The Ada programming language was one of the first to do so.

False

In a loosely coupled system, a job may move from one processor to another during execution.

True

In a master/slave system, the master processor is responsible for managing the entire system—all files, devices, memory, and processors.

data

In general, parallel systems can be put into two broad categories: ____ level parallelism and instruction level parallelism.

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.

False

In parallel computations, mutual exclusion is achieved automatically because each operation is handled in order, one at a time.

True

Java technology is used for many Web and Internet applications, and it integrates well with browsers that can run Java applets with audio, video, and animation directly in a Web page.

True

Java uses both a compiler and an interpreter.

machine cycle

Lock and key synchronization must take place within a single ____.

lightweight processes

Most current operating systems support the implementation of threads, or ____, which have become part of numerous application packages.

True

Multiprocessing can refer to one job using several processors to execute sets of instructions in parallel.

True

Parallel processing is a situation in which two or more processors operate in one system at the same time and may or may not work on related activities.

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.

Thread

The Java ____ class is a collection of methods used to start, run, stop, and check the status of a thread.

loosely coupled

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

master/slave

The ____ multiprocessing configuration is an asymmetric system.

symmetric

The ____ multiprocessing configuration is the most difficult to implement because the processes must be well synchronized to avoid races and deadlocks.

True

The classic problem of producers and consumers is one in which one or more processes produce some data that one or more processes consume later.

True

The common element in all synchronization schemes is to allow a process to finish work on a critical region of the program before other processes have access to it.

True

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

False

The master/slave configuration is a symmetric multiprocessing system.

False

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

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.

False

The primary disadvantage of the WAIT and SIGNAL operation set is that it does not address busy waiting.

bytecodes

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

False

The success of process synchronization hinges on the capability of the operating system to make a resource available to other processes while it is being used by one of them.

P and V

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

False

The two operations that can be performed on a semaphore variable are select and increment (P and V).

mutex

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

implicit parallelism

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

False

When a programmer indicates in the code which instructions can be executed in parallel in a program (for example, using COBEGIN and COEND), it is called implicit parallelism.

True

When multiprocessing takes place at the thread level, a high degree of synchronization is required to disassemble each process.

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.

Hoare

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

Three

____ semaphores are used in the producer and consumer problem.

Two

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

Busy Waiting

a method by which processes, waiting for an event to occur, continuously test to see if the condition has changed and remain in unproductive, resource-consuming wait loops.

Wait and Signal

a modification of the test-and-set synchronization mechanism that's designed to remove busy waiting

Critical Region

a part of the program that must complete execution before other processes can begin.

Test and Set

an indivisible machine instruction, which is executed in a single machine cycle to determine whether the processor is available.

Concurrent Processin

execution by a single processor of a set of processes in such a way that they appear to be happening at the same time.

Process Synchronization

the need for algorithms to resolve conflicts between processors in a multiprocessing environment; or (2) the need to ensure that events occur in the proper order if they are carried out by several processes.

Multiprocessing(CH6)

when two or more processors share system resources that may include some or all of the following: the same main memory, I/o devices, and control program routines.