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OS Final Possible Questions

Beschreibung

Information Technology Quiz am OS Final Possible Questions, erstellt von Matt Merritt am 01/05/2017.
Matt Merritt
Quiz von Matt Merritt, aktualisiert more than 1 year ago
Matt Merritt
Erstellt von Matt Merritt vor etwa 7 Jahre
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Zusammenfassung der Ressource

Frage 1

Frage
An SMP can be defined as a stand-alone computer system with two or more similar processors of comparable capability.
Antworten
  • True
  • False

Frage 2

Frage
Over the years memory access speed has consistently increased more rapidly than processor speed.
Antworten
  • True
  • False

Frage 3

Frage
The ___ chooses which block to replace when a new block is to be loaded into the cache and the cache already has all the slots filled with other blocks.
Antworten
  • memory controller
  • mapping function
  • write policy
  • replacement algorithm

Frage 4

Frage
When an external device becomes ready to be serviced by the processor, the device sends a(n) ___ signal to the processor.
Antworten
  • access
  • halt
  • handler
  • interrupt

Frage 5

Frage
The ____ holds the address of the next instruction.
Antworten
  • Accumulator (AC)
  • Instruction Register (IR)
  • Instruction Counter (IC)
  • Program Counter (PC)

Frage 6

Frage
Small, fast memory located between the processor and main memory is called ____.
Antworten
  • Block memory
  • Cache memory
  • Direct memory
  • WORM memory

Frage 7

Frage
One mechanism Intel uses to make its caches more effective is _______.
Antworten
  • mapping
  • handling
  • interconnecting
  • prefetching

Frage 8

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In a uniprocessor system, multiprogramming increases processor efficiency by _____.
Antworten
  • taking advantage of time wasted by long wait interrupt handling
  • disabling all interrupts execpt those of highest priority
  • eliminating all idle processor cycles
  • increasing processor speed

Frage 9

Frage
The processor controls the operation of the computer and performs its data processing functions.
Antworten
  • True
  • False

Frage 10

Frage
Instruction processing consists of two steps:
Antworten
  • fetch and execute
  • instruction and execute
  • instruction and halt
  • fetch and instruction

Frage 11

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The ____ is the external data by which the OS is able to supervise and control the process.
Antworten
  • execution context
  • associated data
  • executable program
  • nucleus

Frage 12

Frage
The processor itself is not a resource so the OS is not involved in determining how much of the processor time is devoted to the execution of a user.
Antworten
  • True
  • False

Frage 13

Frage
Multiprogramming operating systems are fairly sophisticated compared to single-program or _____ systems.
Antworten
  • time-sharing
  • uniprogramming
  • multitasking
  • memory management

Frage 14

Frage
Hardware features desirable in a batch-processing OS include memory protection, timer, privileged instructions and ______.
Antworten
  • clock cycles
  • associated data
  • interrupts
  • kernels

Frage 15

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• A common strategy to give each process in the queue some time in turn is referred to as a _____ technique.
Antworten
  • multi-threading
  • serial processing
  • time slicing
  • round-robin

Frage 16

Frage
The technique where a system clock generates interrupts, and at each clock interrupt the OS regains control and assigns the processor to another user is _____.
Antworten
  • clock cycle
  • time slicing
  • round-robin
  • multithreading

Frage 17

Frage
______ is where the OS must prevent independent processes from interfering with each other’s memory, both data and instructions.
Antworten
  • Protection and access control
  • Support of modular programming
  • Process isolation
  • Automatic allocation and management

Frage 18

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The phrase "control is passed to a job" means that the processor is now fetching and executing instructions from the monitor program.
Antworten
  • True
  • False

Frage 19

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The key to success of Linux has been its availability for free under the auspice of the _______.
Antworten
  • World Wide Web Consortium
  • Free Software Foundation
  • Berkeley Software Distribution
  • GNU Public License

Frage 20

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Both batch processing and time-sharing use multiprogramming.
Antworten
  • True
  • False

Frage 21

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If a system does not employ virtual memory each process to be executed must be fully loaded into main memory.
Antworten
  • True
  • False

Frage 22

Frage
It is the principal responsibility of the ____ to control the execution of processes.
Antworten
  • OS
  • process control block
  • memory
  • dispatcher

Frage 23

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The ____ is the less-privileged mode.
Antworten
  • user mode
  • kernel mode
  • system mode
  • control mode

Frage 24

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The portion of the operating system that selects the next process to run is called the ____.
Antworten
  • trace
  • process control block
  • dispatcher
  • PSW

Frage 25

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The collection of program, data, stack, and attributes is referred to as the ____.
Antworten
  • process structure
  • process control block
  • process location
  • process image

Frage 26

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A process in the [blank_start]ready[blank_end] state is in main memory and available for execution.
Antworten
  • ready

Frage 27

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The process control block is the least important data structure in an OS.
Antworten
  • True
  • False

Frage 28

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When a process is in the ____ state it is in secondary memory but is available for execution as soon as it is loaded into main memory.
Antworten
  • Blocked
  • Blocked/Suspend
  • Ready
  • Ready/Suspend

Frage 29

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A total of ____ process states are recognized by the UNIX SVR4 operating system.
Antworten
  • 3
  • 9
  • 21
  • 15

Frage 30

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The principal function of the OS is to create, manage, and terminate processes.
Antworten
  • True
  • False

Frage 31

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In a multithreaded environment, a _____ is defined as the unit of resource allocation and a unit of protection.
Antworten
  • strand
  • process
  • string
  • trace

Frage 32

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_____ is a good example of an OS using a combined ULT/KLT approach.
Antworten
  • TRIX
  • Windows
  • LINUX
  • Solaris

Frage 33

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A ____ is a user-created unit of execution within a process.
Antworten
  • Kernel
  • KLT
  • lightweight process
  • ULT

Frage 34

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The _____ are the fundamental entities that can be scheduled and dispatched to run on one of the system processors.
Antworten
  • Processes
  • Kernel threads
  • LWPs
  • ULTs

Frage 35

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A ____ is a dispatchable unit of work that executes sequentially and is interruptible so that the processor can turn to another thread.
Antworten
  • port
  • process
  • token
  • thread

Frage 36

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A Windows process must contain at least ___ thread(s) to execute.
Antworten
  • four
  • three
  • two
  • one

Frage 37

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It takes less time to terminate a process than a thread.
Antworten
  • True
  • False

Frage 38

Frage
The blocked state in which the process is waiting for an event, such as the end of an I/O operation, the availability of a resource, or a signal from another process is the ____ state.
Antworten
  • Times and timers
  • Uninterruptible
  • Stopped
  • Interruptible

Frage 39

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The ____ state is when the thread has terminated.
Antworten
  • ZOMBIE
  • FREE
  • STOP
  • SLEEP

Frage 40

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Any alteration of a resource by one thread affects the environment of the other threads in the same process.
Antworten
  • True
  • False

Frage 41

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As an extension of the principles of modular design and structured programming, some applications can be effectively programmed as a set of concurrent processes.
Antworten
  • True
  • False

Frage 42

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A situation in which a runnable process is overlooked indefinitely by the scheduler, although it is able to proceed, is _____.
Antworten
  • mutual exclusion
  • deadlock
  • starvation
  • livelock

Frage 43

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A semaphore that does not specify the order in which processes are removed from the queue is a _____ semaphore.
Antworten
  • weak
  • general
  • strong
  • binary

Frage 44

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A ____ is a data type that is used to block a process or thread until a particular condition is true.
Antworten
  • deadlock
  • general semaphore
  • condition variable
  • mutex

Frage 45

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The _____ is a programming language construct that provides equivalent functionality to that of semaphores and is easier to control.
Antworten
  • atomic operation
  • co-routine
  • critical section
  • monitor

Frage 46

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The requirement that when one process is in a critical section that accesses shared resources, no other process may be in a critical section that accesses any of those shared resources is ____.
Antworten
  • critical section
  • linelock
  • mutual exclusion
  • atomic operation

Frage 47

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The sharing of main memory among processes is useful to permit efficient and close interaction among processes because such sharing does not lead to any problems.
Antworten
  • True
  • False

Frage 48

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The case of cooperation by sharing covers processes that interact with other processes without being explicitly aware of them.
Antworten
  • True
  • False

Frage 49

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The management of multiple processes within a uniprocessor system is ___.
Antworten
  • multiprogramming
  • structured applications
  • disturbed processing
  • multi-management processing

Frage 50

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The term ____ refers to a technique in which a process can do nothing until it gets permission to enter its critical section but continues to execute an instruction or set of instructions that tests the appropriate variable to gain entrance.
Antworten
  • spin waiting
  • general semaphore
  • critical resource
  • message passing

Frage 51

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The most common technique used for protecting a critical section in Linux is the _____.
Antworten
  • singal
  • atomic bitmap operation
  • atomic integer operation
  • spinlock

Frage 52

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Interrupts, signals, messages, and information in I/O buffers are all example of reusable resources.
Antworten
  • True
  • False

Frage 53

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Requested resources are granted to processes whenever possible with _____.
Antworten
  • deadlock detection
  • preemption
  • mutual exclusion
  • deadlock avoidance

Frage 54

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The ____ allows multiple threads to have simultaneous read-only access to an object protected by the lock.
Antworten
  • barrier
  • condition variable
  • readers/writer lock
  • mutex

Frage 55

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Examples of ___ include processors, I/O channels, main and secondary memory, devices, and data structures such as files, databases, and semaphores.
Antworten
  • regional resources
  • joint resources
  • reusable resources
  • consumable resources

Frage 56

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A closed chain of processes exists, such that each process holds at least one resource needed by the next process in the chain is the condition of ____.
Antworten
  • no preemption
  • mutual exclusion
  • circular wait
  • hold and wait

Frage 57

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The strategy of deadlock ____ is to design a system in such a way that the possibility of deadlock is excluded.
Antworten
  • prevention
  • detection
  • diversion
  • avoidance

Frage 58

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One of the most significant contributions of UNIX to the development of operating systems is the ____.
Antworten
  • semaphore
  • pipe
  • message
  • shared memory

Frage 59

Frage
Deadlock is permanent because none of the events are ever triggered.
Antworten
  • True
  • False

Frage 60

Frage
The fastest form of inter-process communication provided in UNIX is ____.
Antworten
  • shared memory
  • message
  • pipe
  • semaphore

Frage 61

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In a multiprogramming system the available main memory is not generally shared among a number of processes.
Antworten
  • True
  • False

Frage 62

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A ____ is a particular example of logical addresses in which the address is expressed as a location relative to some known point, usually a value in a processor register.
Antworten
  • logical address
  • relative address
  • absolute address
  • physical address

Frage 63

Frage
The page table for each process maintains ____.
Antworten
  • the physical memory location of the process
  • the frame location for each page of the process
  • the page location for each frame of the process
  • the logical memory location of the process

Frage 64

Frage
In a system employing a segmentation scheme for memory management a process is divided into ___
Antworten
  • one segment per thread
  • a number of threads
  • a number of segments which need not be of equal size
  • a number of segments which must be of equal size

Frage 65

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Available chunks of memory are known as ____.
Antworten
  • frames
  • segments
  • addresses
  • pages

Frage 66

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In a multiprogramming environment the programmer knows at the time of coding how much space will be available and where that space will be.
Antworten
  • True
  • False

Frage 67

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In a system employing a segmentation scheme for memory management wasted space is due to _____.
Antworten
  • frames of different sizes
  • external fragmentation
  • internal fragmentation
  • segments of different sizes

Frage 68

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In the Dynamic Partitioning technique of memory management, the placement algorithm that scans memory from the location of the last placement and choose the next available block that is large enough to satisfy the request is called _____>
Antworten
  • next-fit
  • first-fit
  • last-fit
  • best-fit

Frage 69

Frage
In a system employing a paging scheme for memory management wasted space is due to _____.
Antworten
  • internal fragmentation
  • pages of different specified sizes
  • external fragmentation
  • frames of different specified sizes

Frage 70

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One technique for overcoming external fragmentation is ____.
Antworten
  • loading
  • compaction
  • relocation
  • partitioning

Frage 71

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Segments may be of unequal, indeed dynamic, size.
Antworten
  • True
  • False

Frage 72

Frage
A ____ is issued if a desired page is not in main memory.
Antworten
  • paging error
  • paging replacement policy
  • page fault
  • page placement policy

Frage 73

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The ____ determines when a page should be brought into main memory.
Antworten
  • page fault
  • fetch policy
  • working set
  • resident set management

Frage 74

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The ____ policy results in the fewest number of page faults.
Antworten
  • optimal
  • FIFO
  • clock
  • LRU

Frage 75

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The ____ algorithm requires a use bit to be associated with each page in memory.
Antworten
  • page placement
  • working set
  • VSWS
  • page fault frequency

Frage 76

Frage
The ____ structure indexes page table entries by frame number rather than by virtual page number.
Antworten
  • hash table
  • inverted page table
  • page table
  • segment table

Frage 77

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The principle of locality states that program and data references within a process do not tend to cluster.
Antworten
  • True
  • False

Frage 78

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______ is transparent to the programmer and eliminates external fragmentation providing efficient use of main memory.
Antworten
  • Hashing
  • Paging
  • Segemention
  • Thrashing

Frage 79

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____ is a range memory addresses available to a process.
Antworten
  • Address space
  • Real address
  • Virtual address
  • Virtual address space

Frage 80

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____ allows the programmer to view memory as consisting of multiple address spaces.
Antworten
  • Paging
  • Locality
  • Segmentation
  • Resident set managment

Frage 81

Frage
Which of the following scheduling policies allow the OS to interrupt the currently running process and move it to the Ready state?
Antworten
  • FIFO
  • FCFS
  • non-preemptive
  • preemptive

Frage 82

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The strategy that schedules processes based on their group affiliation is generally referred to as ______.
Antworten
  • shortest process next
  • fair share scheduling
  • queuing analysis
  • simulation modeling

Frage 83

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The ____ specifies the instants in time at which the selection function is exercised.
Antworten
  • decision mode
  • medium-term scheduling
  • ready state
  • TAT

Frage 84

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This is a decision whether to add a process to those that are at least partially in main memory and therefore available for execution.
Antworten
  • short-term scheduling
  • long-term scheduling
  • medium-term scheduling
  • I/O scheduling

Frage 85

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Typically, the swapping-in function for processes is based on the need to manage ____.
Antworten
  • the degree of multiprogramming
  • I/O requirements
  • process priorities
  • virtual memory

Frage 86

Frage
Response time in an interactive system is an example of:
Antworten
  • user-oriented criteria for long-term scheduling policies
  • system-oriented criteria for short-term scheduling policies
  • system-oriented criteria for long-term scheduling policies
  • user-oriented criteria for short-term scheduling policies

Frage 87

Frage
A risk with ____ is the possibility of starvation for longer processes, as long as there is a steady supply of shorter processes.
Antworten
  • SRT
  • SPN
  • FIFO
  • FCFS

Frage 88

Frage
First-come-first-served (FCFS) is a simple scheduling policy that tends to favor I/O bound processes over processor bound processes.
Antworten
  • True
  • False

Frage 89

Frage
The traditional UNIX scheduler divides processes into fixed bands of priority levels, with the highest priority band being the ____.
Antworten
  • user process band
  • swapper band
  • file manipulation band
  • utilization band

Frage 90

Frage
One problem with a pure priority scheduling scheme is that lower-priority processes may suffer starvation.
Antworten
  • True
  • False

Frage 91

Frage
The multiprocessor system which consists of a set or processors that share a common main memory and are under the integrated control of an operation system is a _____.
Antworten
  • tightly coupled multiprocessor
  • cluster
  • functionally specialized processor
  • loosely coupled or distributed multiprocessor

Frage 92

Frage
_____ perform static analysis of feasible schedules of dispatching with the result of the analysis being a schedule that determines, at run time, when a task must begin execution.
Antworten
  • Static priority-driven preemptive approaches
  • Static table-drive approaches
  • Dynamic planning-based approaches
  • Dynamic best effort approaches

Frage 93

Frage
The basic idea of _____ is that a lower-priority task inherits the priority of any higher-priority task pending on a resource they share.
Antworten
  • priority ceiling
  • priority inversion
  • unbounded priority inversion
  • priority inheritance

Frage 94

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User control is a generally much broader in an ordinary operating system than in a real-time operating system.
Antworten
  • True
  • False

Frage 95

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With coarse and ____ grained parallelism, there is a synchronization among processes, but at a very gross level.
Antworten
  • medium
  • fine
  • independent
  • very course

Frage 96

Frage
The ____ approach is a set of related threads scheduled to run on a set of processors at the same time, on a one-to-one basis.
Antworten
  • dynamic scheduling
  • load sharing
  • gang scheduling
  • dedicated processor assignment

Frage 97

Frage
The ____ class is intended for applications that will only consume processor time when no other threads are ready to execute.
Antworten
  • idle user
  • time sharing
  • bottom-half kernel
  • real-time

Frage 98

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______ is the time required to execute the task to completion.
Antworten
  • Processing time
  • Priority
  • Resource requirements
  • Ready time

Frage 99

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Processes at ____ priority levels are guaranteed to be selected to run before any time-sharing process but must defer to real-time processes.
Antworten
  • kernel
  • time-sharing
  • real-time
  • load-sharing

Frage 100

Frage
With independent parallelism there is an explicit synchronization among processes.
Antworten
  • True
  • False

Frage 101

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The advantage of ____ is that it provides extremely high data availability.
Antworten
  • RAID 2
  • RAID 4
  • RAID 0
  • RAID 6

Frage 102

Frage
On a movable-head system, the time it takes to position the head at the track is known as
Antworten
  • access time
  • seek time
  • transfer time
  • rotational delay

Frage 103

Frage
The disk scheduling algorithm that implements two sub-queues in a measure to avoid the problem of "arm stickiness" is the ______.
Antworten
  • C-SCAN policy
  • FSCAN policy
  • DMA
  • N-step-SCAN policy

Frage 104

Frage
_____ external devices are suitable for communicating with modems.
Antworten
  • Human-readable
  • Application
  • Machine-readable
  • Communication

Frage 105

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The simplest type of support that the operating system can provide is _____.
Antworten
  • overflow buffering
  • dual buffering
  • single buffering
  • circular buffering

Frage 106

Frage
Cache memory reduces average memory access time by exploiting the principle of locality.
Antworten
  • True
  • False

Frage 107

Frage
RAID 0 provides real-time backups of all data so that in the event of a disk failure, all of the critical data is still immediately available.
Antworten
  • True
  • False

Frage 108

Frage
_____ is a technique that smooths out peaks in I/O demand.
Antworten
  • Buffering
  • Blocking
  • Smoothing
  • Tracking

Frage 109

Frage
The _____ unit is capable of mimicking the processor and of taking over control of the system bus, just like a processor.
Antworten
  • interrupt-driven I/O
  • I/O channel
  • direct memory access
  • programmed I/O

Frage 110

Frage
RAID 5 is organized in a similar fashion to _____, but is different in the fact that RAID 5 distributes the parity strips across all disks.
Antworten
  • RAID 3
  • RAID 2
  • RAID 1
  • RAID 4

Frage 111

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Typically, the only way that a user or application may access files is through the file management system.
Antworten
  • True
  • False

Frage 112

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_____ represents an open file associated with a process.
Antworten
  • Dentry object
  • Inode object
  • File object
  • Superblock object

Frage 113

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An objective of the ____ is to provide a standardized set of I/O interface routines to user processes.
Antworten
  • working directory
  • file management system
  • indexed file allocation
  • file directory

Frage 114

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The ____ is concerned with scheduling disk and tape access to optimize performance.
Antworten
  • device driver
  • basic I/O supervisor
  • access method
  • logical I/O

Frage 115

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The ____ file exploits the capability found on disks to access directly any block of a known address.
Antworten
  • direct
  • sequential
  • indexed sequential
  • indexed

Frage 116

Frage
All types of UNIX files are administered by the OS by means of inodes.
Antworten
  • True
  • False

Frage 117

Frage
The least-complicated form of file organization is the indexed file.
Antworten
  • True
  • False

Frage 118

Frage
The ____ contains the core parts of the operating system, including system binaries, system libraries, and configuration files.
Antworten
  • data directory
  • system directory
  • cache directory
  • mnt/sdcard directory

Frage 119

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A ____ is a contiguous set of allocated blocks.
Antworten
  • key
  • pathname
  • pile
  • portion

Frage 120

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A ___ is the basic element of data.
Antworten
  • database
  • field
  • file
  • record

Frage 121

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General-purpose computer systems far outnumber embedded systems.
Antworten
  • True
  • False

Frage 122

Frage
The ____ module contains the code necessary for processor startup, interrupt delivery, context switching, and other functionality specific to the instruction set architecture of that processor family.
Antworten
  • Variant
  • Platform
  • Memory Management
  • Architechture

Frage 123

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The ____ module includes code for startup, chip selection configuration, interrupt controllers, and timer devices.
Antworten
  • Architechture
  • Variant
  • MMU
  • Platform

Frage 124

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Configurability, direct use of interrupts, and real-time operation are some of the unique characteristics and design requirements for ______/
Antworten
  • Tiny OS
  • eCos
  • embedded operating systems
  • OS service routines

Frage 125

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______ is one of the most widely used embedded operating systems.
Antworten
  • Resource-specific interfaces
  • eCos
  • open sources
  • resource requests

Frage 126

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A key differentiator between desktop/server and embedded Linux distributions is that desktop and server software are typically compiled on one platform but is intended to be executed on another.
Antworten
  • True
  • False

Frage 127

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The _____ interface allows the client to hold on to a resource until the client is notified that someone else needs the resource.
Antworten
  • Resource configure
  • Resource requested
  • Resource
  • Resource-specific

Frage 128

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A mutex is used to enforce mutually exclusive access to a resource, allowing only one thread at a time to gain access.
Antworten
  • True
  • False

Frage 129

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_____ has become a popular approach to implementing wireless sensor network software.
Antworten
  • TinyOS
  • eCos
  • Embedded system
  • Arbiter

Frage 130

Frage
Virtual machines are made up of files.
Antworten
  • True
  • False

Frage 131

Frage
The solution that enables virtualization is a ____.
Antworten
  • round robin
  • virtual machine monitor
  • hyperfile
  • DalviB600

Frage 132

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The ___ facilitates the translation and I/O from the virtual machine to the physical server devices.
Antworten
  • hardware
  • memory
  • hypervisor
  • network interface card

Frage 133

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_____ can power off and on physical hosts as they are needed.
Antworten
  • DRS
  • Storage and Network I/O
  • DPM
  • Resource Scheduler

Frage 134

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The number of guests that can exist on a single hosts is measured as a _____.
Antworten
  • VMM ratio
  • hypervisor ration
  • broker ratio
  • consolidation ratio

Frage 135

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The ____ approach is becoming a common way for businesses and individuals to deal with legacy applications and to optimize their hardware usage.
Antworten
  • virtual machine
  • consolidation
  • ratio
  • round robin

Frage 136

Frage
Virtual machines are hosted via the infrastructure services in the VM kernel.
Antworten
  • True
  • False

Frage 137

Frage
______ is a commercially available hypervisor from VMware that provides users a bare metal hypervisor to host virtal machines on their servers.
Antworten
  • Zygote
  • Dalvi068
  • JVM
  • ESXi

Frage 138

Frage
A key aspect of server virtualization is that VMs cannot be viewed as network resources.
Antworten
  • True
  • False

Frage 139

Frage
The concept of ____, as used in Linux, refers to a partitioning of the privileges available to a root user.
Antworten
  • root isolation
  • hosting platform
  • capabilities
  • processing isolation
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