Exam 1 assignment questions Flashcards
In what way is an operating system like a government?
- It seldom functions correctly.
- It creates an environment within which other programs can do useful work.
- It performs most useful functions by itself.
- It is always concerned primarily with the individual’s needs.
It creates an environment within which other programs can do useful work.
\_\_\_\_ operating systems are designed primarily to maximize resource utilization. PC Handheld computer Mainframe Network
Mainframe
The most common secondary storage devices are ____ (choose two).
- magnetic disk
- random access memory
- solid state disks
- tape drives
- magnetic disk
solid state disks, magnetic disk
Which of the following would lead you to believe that a given system is an SMP-type system?
Each processor is assigned a specific task.
There is a boss–worker relationship between the processors.
Each processor performs all tasks within the operating system.
None of the above
Each processor performs all tasks within the operating system.
A ____ can be used to prevent a user program from never returning control to the operating system.
- portal
- program counter
- firewall
- timer
timer
Embedded computers typically run on a ____ operating system.
- real-time
- Windows XP
- network
- clustered
real-time
Bluetooth and 802.11 devices use wireless technology to communicate over several feet, in essence creating a ____.
- local-area network
- wide-area network
- person-area network
- metropolitan-area network
person-area network
A clustered system ____.
- gathers together multiple CPUs to accomplish computational work
- is an operating system that provides file sharing across a network
- is used when rigid time requirements are present
- can only operate one application at a time
gathers together multiple CPUs to accomplish computational work
Which of the following is a property of peer-to-peer systems?
- Clients and servers are not distinguished from one another.
- Separate machines act as either the client or the server but not both.
- They do not offer any advantages over traditional client-server systems.
- They suffer from the server acting as the bottleneck in performance.
Clients and servers are not distinguished from one another.
Two important design issues for cache memory are \_\_\_\_. speed and volatility -size and replacement policy -power consumption and --reusability -size and access privileges
size and replacement policy
What are some other terms for kernel mode?
- supervisor mode
- system mode
- privileged mode
- All of the above
All of the above
Which of the following statements concerning open source operating systems is true?
- Solaris is open source.
- Source code is freely available.
- They are always more secure than commercial, closed systems.
- All open source operating systems share the same set of goals.
Source code is freely available.
Which of the following operating systems is not open source?
- Windows
- BSD UNIX
- Linux
- PCLinuxOS
Windows
A _____ provides a file-system interface that allows clients to create and modify files.
- compute-server system
- file-server system
- wireless network
- network computer
file-server system
A(n) ____ is a custom build of the Linux operating system.
- LiveCD
- installation
- distribution
- VMWare Player
distribution
__________ is a set of software frameworks that provide additional services to application developers.
- System programs
- Virtualization
- Cloud computing
- Middleware
Middleware
Which statement concerning privileged instructions is considered false?
- They may cause harm to the system.
- They can only be executed in kernel mode.
- They cannot be attempted from user mode.
- They are used to manage interrupts.
They cannot be attempted from user mode.
Which of the following statements is false?
- Mobile devices must be concerned with power consumption.
- Mobile devices can provide features that are unavailable on desktop or laptop computers.
- The difference in storage capacity between a mobile device and laptop is shrinking.
- Mobile devices usually have fewer processing cores than a standard desktop computer.
The difference in storage capacity between a mobile device and laptop is shrinking.
A(n) ________ is the unit of work in a system.
- process
- operating system
- timer
- mode bit
process
The two separate modes of operating in a system are
- supervisor mode and system mode
- kernel mode and privileged mode
- physical mode and logical mode
- user mode and kernel mode
user mode and kernel mode
(true/false)The operating system kernel consists of all system and application programs in a computer.
False
(true/false)Flash memory is slower than DRAM but needs no power to retain its contents.
True
(true/false)A system call is triggered by hardware.
False
(true/false)UNIX does not allow users to escalate privileges to gain extra permissions for a restricted activity.
False
(true/false)Processors for most mobile devices run at a slower speed than a processor in a desktop PC.
True
(true/false)Interrupts may be triggered by either hardware of software.
True
(true/false)A dual-core system requires that each core has its own cache memory.
False
(true/false)Virtually all modern operating systems provide support for SMP.
True
(true/false)All computer systems have some sort of user interaction.
False
(true/false)Solid state disks are generally faster than magnetic disks.
True
(true/false)Solid state disks are considered volatile storage.
False
(true/false)There is no universally accepted definition of an operating system.
True
A \_\_\_\_\_ is an example of a systems program. command interpreter web browser text formatter database system
command interpreter
If a program terminates abnormally, a dump of memory may be examined by a ____ to determine the cause of the problem.
- module
- debugger
- shell
- control card
debugger
A message-passing model is ____.
- easier to implement than a shared memory model for intercomputer communication
- faster than the shared memory model
- a network protocol, and does not apply to operating systems
- only useful for small, simple operating systems
easier to implement than a shared memory model for intercomputer communication
Policy ____.
- determines how to do something
- determines what will be done
- is not likely to change across places
- is not likely to change over time
determines how to do something
The major difficulty in designing a layered operating system approach is ____.
- appropriately defining the various layers
- making sure that each layer hides certain data structures, hardware, and operations from higher-level layers
- debugging a particular layer
- making sure each layer is easily converted to modules
appropriately defining the various layers
A microkernel is a kernel ____.
- containing many components that are optimized to reduce resident memory size
- that is compressed before loading in order to reduce its resident memory size
- that is compiled to produce the smallest size possible when stored to disk
- that is stripped of all nonessential components
that is stripped of all nonessential components
To the SYSGEN program of an operating system, the least useful piece of information is _____.
- the CPU being used
- the amount of memory available
- which applications to install
- operating-system options such as buffer sizes or CPU scheduling algorithms
which applications to install
A boot block ____.
- typically only knows the location and length of the rest of the bootstrap program
- typically is sophisticated enough to load the operating system and begin its execution
- is composed of multiple disk blocks
- is composed of multiple disk cylinders
typically only knows the location and length of the rest of the bootstrap program
_____ provide(s) an interface to the services provided by an operating system.
- Shared memory
- System calls
- Simulators
- Communication
System calls
_____ is not one of the major categories of system calls.
- Process control
- Communications
- Protection
- Security
Security
_____ allow operating system services to be loaded dynamically.
- Virtual machines
- Modules
- File systems
- Graphical user interfaces
Modules
Microkernels use _____ for communication.
- message passing
- shared memory
- system calls
- virtualization
message passing
The close() system call in UNIX is used to close a file. What is the equivalent system call in Windows?
- CloseHandle()
- close()
- CloseFile()
- Exit()
CloseHandle()
The Windows CreateFile() system call is used to create a file. What is the equivalent system call in UNIX?
- ioctl()
- open()
- fork()
- createfile()
open()
Android runs Java programs _____________.
- in the Dalvik virtual machine
- natively
- in the Java virtual machine
- Android does not run Java programs
in the Dalvik virtual machine
______ is a mobile operating system designed for the iPhone and iPad.
- Mac OS X
- Android
- UNIX
- iOS
iOS
The ________ provides a portion of the system call interface for UNIX and Linux.
- POSIX
- Java
- Standard C library
- Standard API
-Standard C library
Which of the following statements is incorrect?
- An operating system provides an environment for the execution of programs.
- An operating system manages system resources.
- Operating systems provide both command line as well as graphical user interfaces.
- Operating systems must provide both protection and security.
Operating systems provide both command line as well as graphical user interfaces.
_____ is/are not a technique for passing parameters from an application to a system call.
- Cache memory
- Registers
- Stack
- Special block in memory
Cache memory
(true/false)KDE and GNOME desktops are available under open-source licenses.
True
(true/false)Many operating systems merge I/O devices and files into a combined file because of the similarity of system calls for each.
True
(true/false)An initial bootstrap program is in the form of random-access memory (RAM).
False
(true/false)System calls can be run in either user mode or kernel mode.
False
(true/false)Application programmers typically use an API rather than directory invoking system calls.
True
(true/false)In general, Windows system calls have longer, more descriptive names, and UNIX system calls use shorter, less descriptive names.
True
(true/false)Mac OS X is a hybrid system consisting of both the Mach microkernel and BSD UNIX.
True
(true/false)iOS is open source, Android is closed source.
False
With round robin scheduling algorithm in a time shared system:
-using very large time slices converts it into First come First served scheduling
algorithm
-using very small time slices converts it into First come First served scheduling
algorithm
-using extremely small time slices increases performance
-using very small time slices converts it into Shortest Job First algorithm
using very large time slices converts it into First come First served scheduling
algorithm
The portion of the process scheduler in an operating system that dispatches processes is
concerned with:
-assigning ready processes to CPU
-assigning ready processes to waiting queue
-assigning running processes to blocked queue
-all of the mentioned
assigning ready processes to CPU
Complex scheduling algorithms:
- are very appropriate for very large computers
- use minimal resources
- use many resources
- all of the mentioned
are very appropriate for very large computers
The FIFO algorithm:
- first executes the job that came in last in the queue
- first executes the job that came in first in the queue
- first executes the job that needs minimal processor
- first executes the job that has maximum processor needs
first executes the job that came in first in the queue
The strategy of making processes that are logically runnable to be temporarily suspended is called:
- Non preemptive scheduling
- Preemptive scheduling
- Shortest job first
- First come First served
-Preemptive scheduling
Scheduling is :
- allowing a job to use the processor
- making proper use of processor
- all of the mentioned
- none of the mentioned
allowing a job to use the processor
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 timesharing
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?
-tQ = 15ms
-tQ = 40ms
-tQ = 45ms
-tQ = 50ms
tQ = 45ms
Orders are processed in the sequence they arrive if _______ rule sequences the jobs.
- earliest due date
- slack time remaining
- first come, first served
- critical ratio
first come, first served
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
-I only
-I and III only
-II and III only
-I, II and III
I, II and III
The most optimal scheduling algorithm is:
- FCFS – First come First served
- SJF – Shortest Job First
- RR – Round Robin
- None of the mentioned
SJF – Shortest Job First
The real difficulty with SJF in short term scheduling is:
- it is too good an algorithm
- knowing the length of the next CPU request
- it is too complex to understand
- none of the mentioned
knowing the length of the next CPU request
The FCFS algorithm is particularly troublesome for ____________
- time sharing systems
- multiprogramming systems
- multiprocessor systems
- operating systems
-multiprogramming systems
Preemptive Shortest Job First scheduling is sometimes called:
- Fast SJF scheduling
- EDF scheduling – Earliest Deadline First
- HRRN scheduling – Highest Response Ratio Next
- SRTN scheduling – Shortest Remaining Time Next
SRTN scheduling – Shortest Remaining Time Next
An SJF algorithm is simply a priority algorithm where the priority is:
- the predicted next CPU burst
- the inverse of the predicted next CPU burst
- the current CPU burst
- anything the user wants
the predicted next CPU burst
One of the disadvantages of the priority scheduling algorithm is that:
- it schedules in a very complex manner
- its scheduling takes up a lot of time
- it can lead to some low priority process waiting indefinitely for the CPU
- none of the mentioned
-it can lead to some low priority process waiting indefinitely for the CPU
‘Aging’ is:
- keeping track of cache contents
- keeping track of what pages are currently residing in memory
- keeping track of how many times a given page is referenced
- increasing the priority of jobs to ensure termination in a finite time
increasing the priority of jobs to ensure termination in a finite time
A solution to the problem of indefinite blockage of low – priority processes is:
- Starvation
- Wait queue
- Ready queue
- Aging
-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.
-i only
-i and iii only
-ii and iii only
-i, ii and iii
i, ii and iii
Which of the following scheduling algorithms gives minimum average waiting time?
- FCFS
- SJF
- Round – robin
- Priority
-SJF
Restricting the child process to a subset of the parent’s resources prevents any
process from :
-overloading the system by using a lot of secondary storage
-under-loading the system by very less CPU utilization
-overloading the system by creating a lot of sub-processes
-crashing the system by utilizing multiple resources
overloading the system by creating a lot of sub-processes
A parent process calling \_\_\_\_\_ system call will be suspended until children processes terminate. -wait -fork -exit -exec
-wait
With _____________ only one process can execute at a time; meanwhile all other
process are waiting for the processor. With ______________ more than one
process can be running simultaneously each on a different processor.
-Multiprocessing, Multiprogramming
-Multiprogramming, Uniprocessing
-Multiprogramming, Multiprocessing
-Uniprogramming, Multiprocessing
Multiprogramming, Multiprocessing
In UNIX, each process is identified by its :
- Process Control Block
- Device Queue
- Process Identifier
- None of the mentioned
Process Identifier
In UNIX, the return value for the fork system call is \_\_\_\_\_ for the child process and \_\_\_\_\_ for the parent process. -A Negative integer, Zero -Zero, A Negative integer -Zero, A nonzero integer -A nonzero integer, Zero
-Zero, A nonzero integer
The child process can:
- be a duplicate of the parent process
- never be a duplicate of the parent process
- cannot have another program loaded into it
- never have another program loaded into it
be a duplicate of the parent process
A Process Control Block(PCB) does not contain which of the following:
- Code
- Stack
- Bootstrap program
- Data
-Bootstrap program
The number of processes completed per unit time is known as \_\_\_\_\_\_\_\_\_\_ Output Throughput Efficiency Capacity
Throughput
The state of a process is defined by:
The current activity of the process
Which of the following is not the state of a process? New Old Waiting Running
Old
The Process Control Block is: Process type variable Data Structure A secondary storage section A Block in memory
Data Structure
The degree of multi-programming is:
- the number of processes executed per unit time
- the number of processes in the ready queue
- the number of processes in the I/O queue
- the number of processes in memory
-the number of processes in memory
A single thread of control allows the process to perform: only one task at a time multiple tasks at a time only two tasks at a time all of the mentioned
only one task at a time
The objective of multi-programming is to:
Have some process running at all times
Which of the following do not belong to queues for processes? Job Queue PCB queue Device Queue Ready Queue
PCB queue
When the process issues an I/O request : It is placed in an I/O queue It is placed in a waiting queue It is placed in the ready queue It is placed in the Job queue
It is placed in an I/O queue
What is a long-term scheduler ?
It selects which process has to be brought into the ready queue
It selects which process has to be executed next and allocates CPU
It selects which process to remove from memory by swapping
None of the mentioned
It selects which process has to be brought into the ready queue
If all processes I/O bound, the ready queue will almost always be ______ and the
Short term Scheduler will have a ______ to do.
full,little
full,lot
empty,little
empty,lot
empty,little
What is a medium-term scheduler?
It selects which process has to be brought into the ready queue
It selects which process has to be executed next and allocates CPU
It selects which process to remove from memory by swapping
None of the mentioned
It selects which process to remove from memory by swapping
What is a short-term scheduler ?
It selects which process has to be brought into the ready queue
It selects which process has to be executed next and allocates CPU
It selects which process to remove from memory by swapping
None of the mentioned
It selects which process has to be executed next and allocates CPU
The primary distinction between the short term scheduler and the long term scheduler is : The length of their queues The type of processes they schedule The frequency of their execution None of the mentioned
The frequency of their execution
In a time-sharing operating system, when the time slot given to a process is
completed, the process goes from the running state to the :
Blocked state
Ready state
Suspended state
Terminated state
Ready state
In a multi-programming environment :
the processor executes more than one process at a time
the programs are developed by more than one person
more than one process resides in the memory
a single user can execute many programs at the same time
more than one process resides in the memory
Suppose that a process is in “Blocked” state waiting for some I/O service. When
the service is completed, it goes to the :
Running state
Ready state
Suspended state
Terminated state
Ready state
The context of a process in the PCB of a process does not contain : the value of the CPU registers the process state memory-management information context switch time
context switch time
