414 Chapter 2

Emulation

Allows an OS to run on non-native hardware

Describe the services an operating system can provide.

An operating system can provide users and programs services. It provides programs an environment to execute and allows the users to execute the programs in convenient manner.

_____ allow operating system services to be loaded dynamically. A) Virtual machines B) Modules C) File systems D) Graphical user interfaces

B) Modules

The strategy of making processes that are logically runable to be temporarily suspended is called: A) Non preemptive scheduling B) Preemptive scheduling C) Shortest job first D) First come First served

B) Preemptive scheduling

Which of the following scheduling algorithms gives minimum average waiting time? A) FCFS B) SJF C) Round - robin D) Priority

B) SJF

The most optimal scheduling algorithm is: A) FCFS - First come First served B) SJF - Shortest Job First C) RR - Round Robin D) None of the mentioned

B) SJF - Shortest Job First

_____ provide(s) an interface to the services provided by an operating system. A) Shared memory B) System calls C) Simulators D) Communication

B) System calls

If a program terminates abnormally, a dump of memory may be examined by a ____ to determine the cause of the problem. A) module B) debugger C) shell D) control card

B) debugger

Policy ____. A) determines how to do something B) determines what will be done C) is not likely to change across places D) is not likely to change over time

B) determines what will be done

The FIFO algorithm: A) first executes the job that came in last in the queue B) first executes the job that came in first in the queue C) first executes the job that needs minimal processor D) first executes the job that has maximum processor needs

B) first executes the job that came in first in the queue

The real difficulty with SJF in short term scheduling is: A) it is too good an algorithm B) knowing the length of the next CPU request C) it is too complex to understand D) none of the mentioned

B) knowing the length of the next CPU request

The FCFS algorithm is particularly troublesome for ____________ A) time sharing systems B) multiprogramming systems C) multiprocessor systems D) operating systems

B) multiprogramming systems

The Windows CreateFile() system call is used to create a file. What is the equivalent system call in UNIX? A) ioctl() B) open() C) fork() D) createfile()

B) open()

Which of the following statements is incorrect? A) An operating system provides an environment for the execution of programs. B) An operating system manages system resources. C) Operating systems provide both command line as well as graphical user interfaces. D) Operating systems must provide both protection and security.

C) Operating systems provide both command line as well as graphical user interfaces.

The ________ provides a portion of the system call interface for UNIX and Linux. A) POSIX B) Java C) Standard C library D) Standard API

C) Standard C library

Orders are processed in the sequence they arrive if _______ rule sequences the jobs. A) earliest due date B) slack time remaining C) first come, first served D) critical ratio

C) first come, first served

The Windows CreateProcess() system call creates a new process. What is the equivalent system call in UNIX? A) NTCreateProcess() B) process() C) fork() D) getpid()

C) fork()

Explain why a modular kernel may be the best of the current operating system design techniques.

Normal kernels load everything with a user boots whatever system/hardware routine. Whereas modular kernels are divided and only the kernel that is needed is called.

DTrace

A code to record amount of time each process with USERID 101 is running in nanoseconds

GRUB

A common bootstrap loader allowing selection of kernel from multiple disks, versions, kernel options

_____ is/are not a technique for passing parameters from an application to a system call. A) Cache memory B) Registers C) Stack D) Special block in memory

A) Cache memory

The close() system call in UNIX is used to close a file. What is the equivalent system call in Windows? A) CloseHandle() B) close() C) CloseFile() D) Exit()

A) CloseHandle()

Scheduling is : A) allowing a job to use the processor B) making proper use of processor C) all of the mentioned D) none of the mentioned

A) allowing a job to use the processor

The major difficulty in designing a layered operating system approach is ____. A) appropriately defining the various layers B) making sure that each layer hides certain data structures, hardware, and operations from higher-level layers C) debugging a particular layer D) making sure each layer is easily converted to modules

A) appropriately defining the various layers

Complex scheduling algorithms: A) are very appropriate for very large computers B) use minimal resources C) use many resources D) all of the mentioned

A) are very appropriate for very large computers

The portion of the process scheduler in an operating system that dispatches processes is concerned with: A) assigning ready processes to CPU B) assigning ready processes to waiting queue C) assigning running processes to blocked queue D) all of the mentioned

A) assigning ready processes to CPU

A _____ is an example of a systems program. A) command interpreter B) web browser C) text formatter D) database system

A) command interpreter

A message-passing model is ____. A) easier to implement than a shared memory model for inter-computer communication B) faster than the shared memory model C) a network protocol, and does not apply to operating systems D) only useful for small, simple operating systems

A) easier to implement than a shared memory model for inter-computer communication

Android runs Java programs _____________. A) in the Dalvik virtual machine B) natively C) in the Java virtual machine D) Android does not run Java programs

A) in the Dalvik virtual machine

Microkernels use _____ for communication. A) message passing B) shared memory C) system calls D) virtualization

A) message passing

An SJF algorithm is simply a priority algorithm where the priority is: A) the predicted next CPU burst B) the inverse of the predicted next CPU burst C) the current CPU burst D) anything the user wants

A) the predicted next CPU burst

A boot block ____. A) typically only knows the location and length of the rest of the bootstrap program B) typically is sophisticated enough to load the operating system and begin its execution C) is composed of multiple disk blocks D) is composed of multiple disk cylinders

A) typically only knows the location and length of the rest of the bootstrap program

With round robin scheduling algorithm in a time shared system, A) using very large time slices converts it into First come First served scheduling algorithm B) using very small time slices converts it into First come First served scheduling algorithm C) using extremely small time slices increases performance D) using very small time slices converts it into Shortest Job First algorithm

A) using very large time slices converts it into First come First served scheduling algorithm

What are the advantages and disadvantages of using a microkernel approach?

Advantages: ease of extending the operating system, more security and reliability. Disadvantages: suffers from performance decreases due to increased system function overhead.

One of the disadvantages of the priority scheduling algorithm is that: A) it schedules in a very complex manner B) its scheduling takes up a lot of time C) it can lead to some low priority process waiting indefinitely for the CPU D) none of the mentioned

C) it can lead to some low priority process waiting

There are 10 different processes running on a workstation. Idle processes are waiting for an input event in the input queue. Busy processes are scheduled with the Round-Robin time sharing method. Which out of the following quantum times is the best value for small response times, if the processes have a short runtime, e.g. less than 10ms? A) tQ = 15ms B) tQ = 40ms C) tQ = 45ms D) tQ = 50ms

C) tQ = 45ms

To the SYSGEN program of an operating system, the least useful piece of information is _____. A) the CPU being used B) the amount of memory available C) which applications to install D) operating-system options such as buffer sizes or CPU scheduling algorithms

C) which applications to install

Hybrid Systems

Combines multiple approaches to address performance, security and usability needs

A solution to the problem of indefinite blockage of low - priority processes is: A) Starvation B) Wait queue C) Ready queue D) Aging

D) Aging

Which of the following statements are true? I. Shortest remaining time first scheduling may cause starvation II. Preemptive scheduling may cause starvation III. Round robin is better than FCFS in terms of response time A) I only B) I and III only C) II and III only D) I, II and III

D) I, II and III

Preemptive Shortest Job First scheduling is sometimes called: A) Fast SJF scheduling B) EDF scheduling - Earliest Deadline First C) HRRN scheduling - Highest Response Ratio Next D) SRTN scheduling - Shortest Remaining Time Next

D) SRTN scheduling - Shortest Remaining Time Next

_____ is not one of the major categories of system calls. A) Process control B) Communications C) Protection D) Security

D) Security

Which of the following statements are true? i) Shortest remaining time first scheduling may cause starvation ii) Preemptive scheduling may cause starvation iii) Round robin is better than FCFS in terns of response time A) i only B) i and iii only C) ii and iii only D) i, ii and iii

D) i, ii and iii

'Aging' is: A) keeping track of cache contents B) keeping track of what pages are currently residing in memory C) keeping track of how many times a given page is referenced D) increasing the priority of jobs to ensure termination in a finite time

D) increasing the priority of jobs to ensure termination in a finite time

A microkernel is a kernel ____. A) containing many components that are optimized to reduce resident memory size B) that is compressed before loading in order to reduce its resident memory size C) that is compiled to produce the smallest size possible when stored to disk D) that is stripped of all nonessential components

D) that is stripped of all nonessential components

T/F An initial bootstrap program is in the form of random-access memory (RAM).

False

T/F System calls can be run in either user mode or kernel mode.

False

T/F iOS is open source, Android is closed source.

False

There are two different ways that commands can be processed by a command interpreter. One way is to allow the command interpreter to contain the code needed to execute the command. The other way is to implement the commands through system programs. Compare and contrast the two approaches?

The first approach is the interpreter loads the right program within the memory along with any needed arguments. The second is when the user issues a command, the interpreter jumps to the correct section of code, executes it, and then returns the control back to the user. Some good things about the first method is that the new commands can be added without changing the command interpreter. But something bad about it is that the same interpreter is reduced in speed. The pros of the second approach is the speed and simplicity. The cons would be that the new commands require rewriting the interpret program which may cause the code to get larger and larger.

Program Execution

The system must be able to load a program into memory and to run that program, end execution, either normally or abnormally (indicating error)

Describe the relationship between an API, the system-call interface, and the operating system.

The system-call interface of any programming language servers as a link to system calls made available by the operating system. The interface intercepts some function calls in the API and the uses those to invoke the correct system call within the operating system. This means that most of the details of the operating-system interface are not available for the programmer to see by the API and are managed by the run-time support library.

SYSGEN

This program obtains information concerning the specific configuration of the hardware system

T/F Application programmers typically use an API rather than directory invoking system calls.

True

T/F In general, Windows system calls have longer, more descriptive names, and UNIX system calls use shorter, less descriptive names.

True

T/F KDE and GNOME desktops are available under open-source licenses.

True

T/F Mac OS X is a hybrid system consisting of both the Mach microkernel and BSD UNIX.

True

T/F Many operating systems merge I/O devices and files into a combined file because of the similarity of system calls for each.

True

MS-DOS

Written to provide the most functionality in the least space

DMA is used for: a) high speed devices (disks and communications network) b) low speed devices c) utilizing CPU cycles d) all of the mentioned

a) high speed devices (disks and communications network)

An interrupt vector a) is an address that is indexed to an interrupt handler b) is a unique device number that is indexed by an address c) is a unique identity given to an interrupt d) none of the mentioned

a) is an address that is indexed to an interrupt handler

How does the Hardware trigger an interrupt? a) sending signals to CPU through system bus b) executing a special program called interrupt program c) executing a special program called system program d) Executing a special operation called system call

a) sending signals to CPU through system bus

In a programmed input/output(PIO): a) the CPU uses polling to watch the control bit constantly, looping to see if device ready b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available c) the CPU receives an interrupt when the device is ready for the next byte d) the CPU runs a user written code and does accordingly

a) the CPU uses polling to watch the control bit constantly, looping to see if device ready

Monolithic kernel

an OS architecture where the entire OS (which includes the device drivers, file system, and the application IPC) is working in kernel space.

In the layered approach of Operating Systems: a) Bottom Layer(0) is the User Interface b) Highest Layer(N) is the User Interface c) Bottom Layer(N) is the hardware c) Highest Layer(N) is the hardware

b) Highest Layer(N) is the User Interface

How does the software trigger an interrupt? a) sending signals to CPU through bus b) executing a special operation called system call c) executing a special program called system program d) executing a special program called interrupt trigger program

b) executing a special operation called system call

What is a trap/exception? a) hardware generated interrupt caused by an error b) software generated interrupt caused by an error c) user generated interrupt caused by an error d) none of the mentioned

b) software generated interrupt caused by an error

In a memory mapped input/output: a) the CPU uses polling to watch the control bit constantly, looping to see if device is ready b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available c) the CPU receives an interrupt when the device is ready for the next byte d) the CPU runs a user written code and does accordingly

b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available

What is an ISR? a) Information Service Request b) Interrupt Service Request c) Interrupt Service Routine d) Information Service Routine

c) Interrupt Service Routine

An interrupt drive input/output: a) the CPU uses polling to watch the control bit constantly, looping to see if device is ready b) the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available c) the CPU receives an interrupt when the device is ready for the next byte d) the CPU runs a user written code and does accordingly

c) the CPU receives an interrupt when the device is ready for the next byte

Which operation is performed by an interrupt handler? a) saving the current state of the system b) loading the interrupt handling code and executing it c) once done handling, bringing back the system to the original state it was before the interrupt occurred d) all of the mentioned

d) all of the mentioned

The initial program that is run when the computer is powered up is called: a) boot program b) boot loader c) initializer d) bootstrap program

d) bootstrap program

______ is a mobile operating system designed for the iPhone and iPad. A) Mac OS X B) Android C) UNIX D) iOS

iOS