Questão 1
Questão
A situation where several processes access and manipulate the same data concurrently and the outcome of the execution depends on the particular order in which access takes place is called:
Responda
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race condition
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data consistency
-
starvation
-
mutual exclusion
Questão 2
Questão
Which one of the following is the address generated by CPU?
Responda
-
logical address
-
physical address
-
absolute address
-
none of the above
Questão 3
Questão
What is the ready state of a process?
Responda
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when process is scheduled to run after some execution
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none of the above
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when process is using CPU
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when process is unable to run until some task has been completed
Questão 4
Questão
Mutual exclusion can be provided by the:
Responda
-
none of the above maint
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mutex locks
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both
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binary semaphores
Questão 5
Questão
What is a long-term scheduler?
Responda
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it selects which process has to be executed next and allocates CPU
-
none of the above
-
it selects which process has to be brought into the ready queue
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it selects which process has to remove from memory by swapping
Questão 6
Questão
Operating system maintains the page table for
Responda
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each process
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each thread
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each instruction
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each address
Questão 7
Questão
If a page number is not found in the TLB, then it is known as a:
Responda
-
TLB miss
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buffer miss
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TLB hit
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page fault
Questão 8
Questão
Part of a program where the shared memory is accessed and which should be executed invisibly, is called:
Responda
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semaphores
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mutual exclusion
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critical section
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directory
Questão 9
Questão
In memory systems, boundary registers?
Responda
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track the beginning and ending of programs
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track page boundaries
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are only necessary with fixed partitions
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are used for temporary program variable storage
Questão 10
Questão
The resource vector defines
Responda
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total amount of resources required for all processes
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total amount of each resource in the system
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total amount of each resource allocated to all processes
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total amount of each resource NOT allocated to any process
Questão 11
Questão
When each process in the set is blocked awaiting for resource seized by another blocked process
Responda
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it is a deadend
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it is a deadlock
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it is a softlock
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it is a mortallock
Questão 12
Questão
The number of resources requested be a process:
Responda
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must exceed the total number of resources available in the system
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must always be equal to the total number of resources available in the system
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must not exceed the total number of resources available in the system
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must always be less than the total number of resources available in the system
Questão 13
Questão
What is interprocess communication?
Responda
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communication between two process
-
communication between two threads of same process
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none of the above
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communication within the process
Questão 14
Questão
The degree of multi-programming is:
Responda
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the number of processes executed per unit time
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the number of processes in the I/O queue
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the number of processes in the ready queue
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the number of processes in memory
Questão 15
Questão
This matrix defines the amount of resources of type j requested by process i
Responda
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Allocation matrix
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Resource matrix
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Request matrix
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Claim matrix
Questão 16
Questão
To avoid the race condition, the number of processes that may be simultaneously inside their critical section is:
Questão 17
Questão
Which process can be affected by other processes executing in the system?
Responda
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init process
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cooperating process
-
child process
-
parent process
Questão 18
Questão
Which of the following registers are used by the processor to exchange data with memory?
Responda
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MAR and MBR
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PC and IR
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Program status word
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I/OAR and I/OBR
Questão 19
Questão
Which of the following registers are used by the processor to exchange data with input/output module?
Responda
-
MAR and MBR
-
PC and IR
-
Program status word
-
I/OAR and I/OBR
Questão 20
Questão
The main disadvantage of this technique: consumes a lot of processor time, because every word
Questão 21
Questão
The processor issues an I/O command to a module and then go on to some other useful work. The I/O module performs the requested action and alerts the processor to request service when it is ready to exchange data with the processor. The described technique is:
Questão 22
Questão
Which of the following is not a technique possible for I/O operations?
Questão 23
Questão
If a page table entry is not in main memory, then it is known as a:
Responda
-
page fault
-
buffer miss
-
TLB hit
-
TLB miss
Questão 24
Questão
We have
Ts = average (system) access time
T1 = access time of M1 (cache)
T2 = access time of M2 (main memory)
T3 = access time of M3 (disk)
H1 = hit ratio, fraction of time reference is found i M1
H2 = hit ratio, fraction of time reference is found i M2
The average time to access an item, in case the item in disk is:
Responda
-
Ts = H1*T1 + H2*T2 + (1-H2)*T3
-
Ts = H1*T1 + (1-H1)*(H1*T1 + H2*(T1 + T2) + (1 - H2)*(T2 + T3))
-
Ts = H1*T1 + (1-H1)*H2*(T2 + T3)
-
Ts = H1*T1 + (1-H1)*(H2*(T1 + T2) + (1 - H2)*(T1 + T2 + T3))
Questão 25
Questão
This chooses which block to replace when a new block is to be loaded into the cache and the cache already had all slots filled with other blocks:
Responda
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replacement algorithm
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write policy
-
cache size
-
locality of reference
Questão 26
Questão
If the accessed word is found in the faster memory, that is defined as a:
Questão 27
Questão
If the accessed word is not found in the faster memory, that is defined as a:
Questão 28
Questão
The processor contains a single data register, called
Questão 29
Questão
Which register contains the instruction most recently fetched?
Responda
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instruction register
-
execution register
-
program counter
-
process counter
Questão 30
Questão
This register specifies the location in memory for the next read or write
Responda
-
Memory address register
-
I/OAR
-
Memory buffer register
-
I/OBR
Questão 31
Questão
Which of the following element of a computer system moves data between the computer and its external environment?
Responda
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Main memory
-
Processor
-
System bus
-
I/O modules
Questão 32
Questão
This main disadvantage of this technique: consumes a lot of processor time, because every word of data that goes from memory to I/O module or from I/O module to memory must pass through the processor
Questão 33
Questão
The processor issues an I/O command to a separate module, by sending the type of operation (read/write), the address of the I/O device, the starting location in memory for data, number of words. Then the processor continues with other work. The module transfers the entire block of data to/from memory without going through the processor. The described technique is:
Questão 34
Questão
The processor issues an I/O command to a module and waits, periodically checking the status of the I/O module until it finds that the operation is complete.
The I/O module performs the requested action and then sets the appropriate bits in the I/O status register but takes no further action to alert the processor.
The described technique is:
Questão 35
Questão
The processor is executing "Load AC from memory" instruction. Choose the correct micro-instruction:
Responda
-
PC -> MAR
M -> MBR
MBR -> AC
IR -> MAR
M -> MBR
MBR -> AC
-
PC -> MBR
M -> MAR
MAR -> IR
IR -> MAR
M -> MBR
MBR -> AC
-
PC -> MAR
M -> MBR
MBR -> IR
IR -> MAR
M -> MBR
MBR -> AC
-
PC -> MAR
M -> MBR
MBR -> IR
IR -> MBR
M -> MAR
MAR -> AC
Questão 36
Questão
If there no interrupts, after each write operation, the processor must:
Responda
-
Load new PC value
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Finish execution of current instruction
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Save the PSW and PC onto control stack
-
Pause and remain idle until the I/O operation finishes
Questão 37
Questão
Complete the relationship concerning the memory systems: greater capacity
Responda
-
lower capacity
-
greater cost per bit
-
faster access speed
-
smaller cost per bit
Questão 38
Questão
User-visible registers minimize main memory references by optimizing register use
Questão 39
Questão
This register contains the data to be written into memory or which receives the data read from memory
Responda
-
I/OAR
-
memory buffer register
-
memory address register
-
I/OBR
Questão 40
Questão
Which of the following element of a computer system controls the operation of the computer and performs its data processing functions?
Responda
-
System bus
-
Main memory
-
I/O modules
-
Processor
Questão 41
Questão
The main disadvantages of this technique: there is a competition for bus usage
Questão 42
Questão
At the beginning of each instruction cycle, the processor fetches an instruction from the memory. The address of the instruction is held in
Questão 43
Questão
The smaller, more expensive, faster memory is:
Responda
-
Disk drive
-
Cache
-
Main memory
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Register
Questão 44
Questão
There were no OS with
Questão 45
Questão
The principal objective of the time-sharing system is to
Questão 46
Questão
Serial processing was used
Questão 47
Questão
The programmer interacted directly with the computer hardware with
Questão 48
Questão
In operation system security and protection, availability is:
Responda
-
Concerned with the proper verification of the identity of users and the validity of messages or data
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Assuring that users cannot read data for which access is unauthorized
-
Protection of data from unauthorized modification
-
Concerned with protecting the system against interruption
Questão 49
Questão
Choose the storage management responsibility for "The OS can achieve efficiency by assigning memory to jobs only as needed"
Responda
-
Process isolation
-
Protection and access control
-
Long-term storage
-
Support of modular programming
-
Automatic allocation and management
Questão 50
Questão
The limit register
Responda
-
Defines the size of the region of memory occupied by the process (in bytes or words)
-
Contains the index into the process list of the process currently controlling the processor
-
Points to the next instruction in that process to be executed
-
Contains the staring address of the region of memory occupied by the process
Questão 51
Questão
In operating system security and protection, authenticity is:
Responda
-
Concerned with the proper verification of the identity of users and the validity of messages or data
-
Assuring that users cannot read data for which access is unauthorized
-
Protection of data from unauthorized modification
-
Concerned with protecting the system against interruption
Questão 52
Questão
An application programs is developed by the
Responda
-
Application programmer
-
End user
-
Operating system
-
Hardware
Questão 53
Questão
"The OS as a User/Computer interface" corresponds to the following objective
Responda
-
Efficiency
-
Convenience
-
Ability to evolve
Questão 54
Questão 55
Questão
If a process is executing in its critical section, then no other processes can be executing in their critical section. This condition is called
Responda
-
Synchronous exclusion
-
Critical exclusion
-
Asynchronous exclusion
-
Mutual exclusion
Questão 56
Questão
In operating system security and protection, confidentiality is:
Responda
-
Concerned with the proper verification of the identity of users and the validity of messages or data
-
Assuring that users cannot read data for which access is unauthorized
-
Protection of data from unauthorized modification
-
Concerned with protecting the system against interruption
Questão 57
Questão
In operating system security and protection, Data integrity is:
Responda
-
Concerned with the proper verification of the identity of users and the validity of messages or data
-
Assuring that users cannot read data for which access is unauthorized
-
Protection of data from unauthorized modification
-
Concerned with protecting the system against interruption
Questão 58
Questão
When the time required for the I/O operation is less that the time to complete the execution of instructions between write operations in the user program, it is:
Responda
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Fast I/O wait
-
Slow I/O wait
-
Long I/O wait
-
Short I/O wait
Questão 59
Questão
This type of memory is nonvolatile:
Responda
-
Register
-
Secondary memory
-
Cache
-
Main memory
Questão 60
Questão
If the contents of a block in the cache are altered, then it is needed to save it back to main memory before replacing it. This is called:
Responda
-
write policy
-
mapping function
-
locality of reference
-
replacement algorithm
Questão 61
Questão
What is not a structural element of a computer system?
Responda
-
System bus
-
Main memory
-
Operating system
-
Processor
Questão 62
Questão
The main disadvantage of this technique: it is a time-consuming process that keeps the processor busy needlessly
Questão 63
Questão
Which of the following element of a computer system stores data and programs
Responda
-
Main memory
-
System bus
-
Processor
-
I/O modules
Questão 64
Questão
When an I/O device completes an I/O operation, the device issues an interrupt signal to the processor and then:
Responda
-
The processor stops execution of the current instruction without finishing it and responds to the interrupt
-
The processor loads the program counter with the entry location of the interrupt-handling routine
-
The processor saves information needed to resume the current program at the point if interrupt
-
The processor finishes execution of the current instruction before responding to the interrupt
Questão 65
Questão
Complete the relationship concerning the memory systems: greater capacity
Responda
-
lower capacity
-
slower access speed
-
greater cost per bit
-
faster access speed
Questão 66
Questão
Which register contains condition codes set by the processor hardware as the result of operations?
Responda
-
Program counter
-
Accumulator
-
Program status word
-
Stack pointer
Questão 67
Questão
Which of the following provides for communication among elements of a computer system?
Responda
-
main memory
-
system bus
-
processor
-
I/O modules
Questão 68
Questão
We have
Ts = average (system) access time
T1 = access time of M1 (cache)
T2 = access time of M2 (main memory)
T3 = access time of M3 (disk)
H1 = hit ratio, fraction of time reference is found i M1
H2 = hit ratio, fraction of time reference is found i M2
The average time to access an item, in case the item in main memory is:
Responda
-
Ts = H1*T1 + H2*T2 + (1-H2)*T3
-
Ts = H1*T1 + (1-H1)*(H1*T1 + H2*(T1 + T2) + (1 - H2)*(T2 + T3))
-
Ts = H1*T1 + (1-H1)*(T1+T2)
-
Ts = H1*T1 + (1-H1)*(H2*(T1 + T2) + (1 - H2)*(T1 + T2 + T3))
Questão 69
Questão
Control and status registers control the operation of the processor and the execution of programs
Questão 70
Questão
This type of system was developed at MIT by a group known as Project MAC for the IBM 709 in 1961
Questão 71
Questão
The concept of codes of operation (user mode, system mode) was introduced with
Questão 72
Questão
Short-term scheduler, or dispatcher, picks a process. Each process in the queue is given some time in turn. This strategy is called:
Responda
-
Round-robin technique
-
Prioritizing
-
Carousel technique
-
Merry-go-round technique
Questão 73
Questão
Central idea in this system was the use of piece of software known as the monitor:
Questão 74
Questão
'More than one program attempts to make use of a shared resource at the same time'. This is
Questão 75
Questão
The term was first used by the designers of Multics in 1960s:
Responda
-
Monitor
-
Process
-
Multiprogramming
-
Time sharing
Questão 76
Responda
-
Application program
-
System programs
-
Opcodes
-
Processor registers
Questão 77
Questão
"When program shares memory and their execution is interleaved by the processor, they may interfere with each other by overwriting common memory areas in unpredictable ways. The result of a particular program depend on the activities of other programs in shared systems".
This is:
Questão 78
Questão
The state of a processor is defined by:
Responda
-
the activity just executed by the process
-
the current activity of the process
-
the final activity of the process
-
the activity to next be executed by the process
Questão 79
Questão
The hardware and software used in providing applications to a user can be viewed in:
Responda
-
classified fashion
-
layered fashion
-
sandwich fashion
-
leveled fashion
Questão 80
Questão
Suppose that a process is in "Blocked" state waiting for some I/O device.
When the service is completed, it goes to the:
Responda
-
Suspended state
-
Terminated state
-
Ready state
-
Running state
Questão 81
Questão
We have
Ts = average (system) access time
T1 = access time of M1 (cache)
T2 = access time of M2 (main memory)
T3 = access time of M3 (disk)
H1 = hit ratio, fraction of time reference is found i M1
H2 = hit ratio, fraction of time reference is found i M2
The average time to access an item, in case the item in cache is:
Responda
-
Ts = H1*T1 + H2*T2 + (1-H2)*T3
-
Ts = H1*T1 + (1-H1)*(H1*T1 + H2*(T1 + T2) + (1 - H2)*(T2 + T3))
-
Ts = H1*T1
-
Ts = H1*T1 + (1-H1)*(H2*(T1 + T2) + (1 - H2)*(T1 + T2 + T3))
Questão 82
Questão
The serial processing presented two main problems:
Responda
-
setup time
-
using a monitor
-
time slicing
-
multiprogramming
-
scheduling
Questão 83
Questão
The process index register:
Responda
-
contains the index into a process list of the process currently controlling the processor
-
define the region in memory occupied by the process
-
points to the next instruction in that process to be executed
-
contains the starting address of the region of memory occupied by the process
Questão 84
Questão
The concept of a batch operating system was developed to
Questão 85
Questão
Batch operating system were used
Questão 86
Questão
"More than one programs hung up waiting for each other".
This is
Questão 87
Questão
This contains the most frequently used functions in the OS:
Questão 88
Questão
The end user views a computer system in terms of:
Questão 89
Questão
Which of the following is not the state of a process?
Responda
-
new
-
waiting
-
terminated
-
ready
-
running
-
old
Questão 90
Questão
The fetched instruction is loaded into the
Questão 91
Questão
When the time required for the I/O operation will take much more time than executing a sequence of user instructions, it is:
Responda
-
Slow I/O wait
-
Long I/O wait
-
Fast I/O wait
-
Short I/O wait
Questão 92
Questão
The system handles multiple interactive jobs
Questão 93
Questão
A system clock generates interrupts at a rate of approximately one every 0.2 seconds. At each clock interrupt, the OS regained control and could assign the processor to another user. This technique is known as
Responda
-
Time scheduling
-
Time sliding
-
Time slicing
-
Time allocating
Questão 94
Questão
Choose the storage management responsibility for "Programmers should be able to define programs modules, and to create, destroy, and alter the size of modules dynamically":
Responda
-
Protection and access control
-
Long-term storage
-
automatic allocation and management
-
process isolation
-
support of modular programming
Questão 95
Questão
'Lost signals, duplicate signals received'. This is