Pregunta 1
Pregunta
What is not a main structural element of a computer system?
Respuesta
-
Processor
-
Main memory
-
System bus
-
Operating bus
Pregunta 2
Pregunta
Which of the following element of a computer system controls the operation of the computer and performs its data processing functions?
Respuesta
-
Processor
-
Main memory
-
System bus
-
I/O modules
Pregunta 3
Pregunta
Which of the following element of a computer system moves data between the the computer and its external environment?
Respuesta
-
Processor
-
Main memory
-
System bus
-
I/O modules
Pregunta 4
Pregunta
Which of the following element of a computer system stores data and programs?
Respuesta
-
Processor
-
Main memory
-
System bus
-
I/O modules
Pregunta 5
Pregunta
Which of the following provides for communication among elements of a computer system?
Respuesta
-
Processor
-
Main memory
-
System bus
-
I/O modules
Pregunta 6
Pregunta
Which of the following registers are used by the processor to exchange data with memory?
Respuesta
-
MAR and MBR
-
I/OAR and I/OBR
-
PC and IR
-
Program status word
Pregunta 7
Pregunta
Which of the following registers are used by the processor to exchange data with input/output module?
Respuesta
-
MAR and MBR
-
I/OAR and I/OBR
-
PC and IR
-
Program status word
Pregunta 8
Pregunta
If the required block is not present in the cache then ______ occurs.
Respuesta
-
cache latency
-
cache hit
-
cache delay
-
cache miss
Pregunta 9
Pregunta
In direct mapping the presence of the block in memory is checked with the help of _____ field.
Pregunta 10
Pregunta
In fully associative mapping, there are the following fields
Respuesta
-
tag, word
-
tag, block, word
-
tag, set, word
-
tag, block
Pregunta 11
Pregunta
The algorithm to remove and place new contents into the cache is called _______
Respuesta
-
Replacement algorithm
-
Renewal algorithm
-
Updation
-
Compaction
Pregunta 12
Pregunta
The bit used to indicate whether the block was recently used or not is _______
Respuesta
-
Control bit
-
Reference bit
-
Dirty bit
-
Valid bit
Pregunta 13
Pregunta
The correspondence between the main memory blocks and those in the cache is given by _________
Respuesta
-
Hash function
-
Mapping function
-
Locale function
-
Assign function
Pregunta 14
Pregunta
The effectiveness of the cache memory is based on the property of ________</
Respuesta
-
Locality of reference
-
Memory localisation
-
Memory size
-
Memory access time
Pregunta 15
Pregunta
The memory blocks are mapped on to the cache with the help of ______
Respuesta
-
Hash functions
-
Write policy
-
Replacement policy
-
Mapping functions
Pregunta 16
Pregunta
The method of mapping the consecutive memory blocks to consecutive cache blocks is called ______
Respuesta
-
Set associative
-
Fully associative
-
Direct
-
Indirect
Pregunta 17
Pregunta
The reason for the implementation of the cache memory is ________
Respuesta
-
To increase the internal memory of the system
-
The difference in speeds of operation of the processor and memory
-
To reduce the memory access and cycle time
-
To increase the memory access and cycle time
Pregunta 18
Pregunta
The spatial aspect of the locality of reference means ________
Respuesta
-
That the recently executed instruction is executed again next
-
That the recently executed won’t be executed again
-
That the instruction executed will be executed at a later time
-
That the instruction in close proximity of the instruction executed will be executed in future
Pregunta 19
Pregunta
The technique of searching for a block by going through all the tags is ______
Respuesta
-
Linear search
-
Binary search
-
Associative search
-
Indirect search
Pregunta 20
Pregunta
The temporal aspect of the locality of reference means ________
Respuesta
-
That the recently executed instruction won’t be executed soon
-
That the recently executed instruction is temporarily not referenced
-
That the recently executed instruction will be executed soon again
-
None of the mentioned
Pregunta 21
Pregunta
This bit indicates if the slot holds a block belonging to the program being executed
Respuesta
-
Control bit
-
Reference bit
-
Dirty bit
-
Valid bit
Pregunta 22
Pregunta
Which is the fastest cache mapping function?
Pregunta 23
Pregunta
While using the direct mapping technique, in a 16 bit system the higher order 5 bits are used for ________
Pregunta 24
Pregunta
The set-associative map technique is a combination of the direct and associative technique
Pregunta 25
Pregunta
We have
Ts = average (system) access time
T1 = access time of M1 (e.g. cache)
T2 = access time of M2 (e.g. main memory)
T3 = access time of M3 (e.g. disk)
H1 = hit ratio, fraction of time reference is found in M1
H2 = hit ratio, fraction of time reference is found in M2
The average time to access an item, in case the item in cache is:
Pregunta 26
Pregunta
We have
Ts = average (system) access time
T1 = access time of M1 (e.g. cache)
T2 = access time of M2 (e.g. main memory)
T3 = access time of M3 (e.g. disk)
H1 = hit ratio, fraction of time reference is found in M1
H2 = hit ratio, fraction of time reference is found in M2
The average time to access an item, in case the item in main memory is:
Pregunta 27
Pregunta
We have
Ts = average (system) access time
T1 = access time of M1 (e.g. cache)
T2 = access time of M2 (e.g. main memory)
T3 = access time of M3 (e.g. disk)
H1 = hit ratio, fraction of time reference is found in M1
H2 = hit ratio, fraction of time reference is found in M2
The average time to access an item, in case the item in disk is:
Respuesta
-
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))
Pregunta 28
Pregunta
All processes share a semaphore variable mutex, initialized to 1. Each process must execute wait(mutex) before entering the critical section and signal(mutex) afterward. Suppose a process executes in the following manner:
singal (mutex);
critical section;
wait (mutex);
In this situation:
Respuesta
-
a deadlock will occur
-
processes will starve to enter critical section
-
several processes maybe executing in their critical section
-
only one process allowed to enter the critical section
Pregunta 29
Pregunta
All processes share a semaphore variable mutex, initialized to 1. Each process must execute wait(mutex) before entering the critical section and signal(mutex) afterward. Suppose a process executes in the following manner:
wait (mutex);
critical section;
wait (mutex);
In this situation:
Respuesta
-
a deadlock will occur
-
processes will starve to enter critical section
-
several processes maybe executing in their critical section
-
only one process allowed to enter the critical section
Pregunta 30
Pregunta
At a particular time of computation the value of a counting semaphore is 7.Then 20 V operations and 15 P operations were completed on this semaphore. The resulting value of the semaphore is:
Pregunta 31
Pregunta
At a particular time of computation the value of a counting semaphore is 7.Then 20 P operations and 15 V operations were completed on this semaphore. The resulting value of the semaphore is
Pregunta 32
Pregunta
The program follows to use a shared binary semaphore T
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
signal (T);
Process B
int Z;
B1 : wait (T);
B2 : Z = X+1;
X = Z;
T is set to 0 before either process begins execution and, as before, X is set to 5. Now, how many different values of X are possible after both processes finish executing ?
Pregunta 33
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=11
Respuesta
-
A1 A2 B1 B2
-
A1 B1 A2 B2
-
A1 B1 B2 A2
-
B1 B2 A1 A2
Pregunta 34
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=6
Respuesta
-
A1 B1 A2 B2
-
A1 B1 B2 A2
-
B1 A1 B2 A2
-
B1 B2 A1 A2
Pregunta 35
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=6?
Respuesta
-
B1 A1 B2 A2
-
B1 A1 A2 B2
-
B1 B2 A1 A2
-
A1 A2 B1 B2
Pregunta 36
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=12?
Respuesta
-
A1 A2 B1 B2
-
B1 A1 B2 A2
-
B1 A1 A2 B2
-
B1 B2 A1 A2
Pregunta 37
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=10?
Respuesta
-
A1 A2 B1 B2
-
A1 B1 B2 A2
-
B1 A1 A2 B2
-
B1 B2 A1 A2
Pregunta 38
Pregunta
The following pair of processes share a common variable X
Process A
int Y;
A1 : Y = X × 2;
A2 : X = Y;
Process B
int Z;
B1: Z = X+1;
B2: X = Z;
X is set to 5 before either process begins execution. As usual, statements within a process are executed sequentially, but statements in process A may execute in any order with respect to statements in process B. Which possible execution path gives X=10?
Respuesta
-
A1 B1 A2 B2
-
B1 A1 B2 A2
-
B1 A1 A2 B2
-
B1 B2 A1 A2
Pregunta 39
Pregunta
Computer programmers are often concerned with synchronization constraints, which are requirements pertaining to the order of events. They are:
Respuesta
-
Serialization and Mutual exclusion
-
Queueing and dispatching
-
Scheduling and dispatching
-
Serialization and Mutual inclusion
Pregunta 40
Pregunta
Concurrent writes:
Respuesta
-
x is a shared variable accessed by two writers
-
x is a local variable accessed by two writers
-
x is a shared variable accessed by two readers
-
x is a shared variable accessed by one writer and one reader
Pregunta 41
Pregunta
If it is not possible to tell, by looking at the program, what will happen when it executes, then the program is
Respuesta
-
non-deterministic
-
non-distributed
-
non-deadlocked
-
non-divisible
Pregunta 42
Pregunta
sem.signal () ...
Pregunta 43
Pregunta 44
Pregunta
Semaphore operation sem.P( ) is alternative to
Respuesta
-
sem.signal
-
sem.wait
-
semaphore initialization
-
semaphore read
Pregunta 45
Pregunta
Semaphore operation sem.V( ) is alternative to
Respuesta
-
sem.signal ( )
-
sem.wait( )
-
semaphore initialization
-
semaphore read
Pregunta 46
Pregunta
Semaphores were invented by
Respuesta
-
Edsger Dijkstra
-
Tim Berners-Lee
-
Vint Cerf
-
Leonard Kleinrock
Pregunta 47
Pregunta
Two events are ______________ if we cannot tell by looking at the program which will happen first
Respuesta
-
Concurrent
-
Constrained
-
Sequential
-
Mutually excluded
Pregunta 48
Respuesta
-
the unit of data exchanged between cache and main memory
-
the unit of data exchanged between cache and registers
-
the unit of data exchanged between registers and main memory
-
the unit of data exchanged between cache and secondary memory
Pregunta 49
Pregunta
If the accessed word is found in the faster memory, that is defined as a:
Pregunta 50
Pregunta
If the accessed word is not found in the faster memory, that is defined as a:
Pregunta 51
Pregunta
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:
Respuesta
-
write policy
-
locality of reference
-
replacement algorithm
-
mapping function
Pregunta 52
Pregunta
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:
Respuesta
-
cache size
-
write policy
-
locality of reference
-
replacement algorithm
Pregunta 53
Pregunta
This determines which cache location the block will occupy:
Respuesta
-
mapping function
-
write policy
-
locality of reference
-
block size
Pregunta 54
Pregunta
When a processor attempts to read a byte or word of memory, it firstly checks the:
Respuesta
-
Cache
-
Main memory
-
Disk
-
CD
Pregunta 55
Pregunta
Which of the following statements is false:
Respuesta
-
compaction does not involve relocation of programs
-
compaction is also known as garbage collection
-
the system must stop everything while it performs the compaction
-
the technique of storage compaction involves moving all occupied areas of storage to one end or other of main storage
Pregunta 56
Respuesta
-
is the device where information is stored
-
is a device that performs a sequence of operations specified by instructions in memory
-
is a sequence of instructions
-
is typically characterized by interactive processing and time-slicing of the CPU's time to allow quick response to each user
Pregunta 57
Respuesta
-
is the device where information is stored
-
is a device that performs a sequence of operations specified by instructions in memory
-
is a sequence of instructions
-
is typically characterized by interactive processing and time-slicing of the CPU's time to allow quick response to each user
Pregunta 58
Respuesta
-
is the device where information is stored
-
is a sequence of instructions
-
is a device that performs a sequence of operations specified by instructions in memory
-
is typically characterized by interactive processing and time-slicing of the CPU's time to allow quick response to each user
Pregunta 59
Pregunta
The memory allocation scheme subject to "external" fragmentation is?
Pregunta 60
Pregunta
The memory allocation scheme subject to "internal" fragmentation is?
Pregunta 61
Pregunta
Any program, no matter how small, will occupy an entire partition results in?
Respuesta
-
internal fragmentation
-
segmentation
-
external fragmentation
-
paging
Pregunta 62
Pregunta
How to solve problem of equal-size partitions?
Pregunta 63
Pregunta
How to solve problem of "external" fragmentation?
Pregunta 64
Respuesta
-
is an access to a page not currently in memory
-
is an error is a specific page
-
occurs when a program accesses a page of memory
-
is a reference to a page belonging to another program
Pregunta 65
Pregunta
Which of the following statements is false?
Respuesta
-
internal fragmentation is increased with small pages
-
a small page size causes large page tables
-
a large page size causes instructions and data that will not be referenced brought into primary storage
-
I/O transfers are more efficient with large pages
Pregunta 66
Respuesta
-
allows each program in turn to use the memory
-
allows many programs to use memory simultaneously
-
does not work with overlaying
-
none of the above
Pregunta 67
Respuesta
-
transferring processes between main memory and secondary memory
-
allows many programs to use memory simultaneously
-
allocate processes in the smallest block of memory
-
none of the above
Pregunta 68
Pregunta
Which of the following is not true about the memory management?
Respuesta
-
virtual memory is used only in multi-user systems
-
segmentation suffers from external fragmentation
-
paging suffers from internal fragmentation
-
segmented memory can be paged
Pregunta 69
Pregunta
Segmentation suffers from external fragmentation?
Pregunta 70
Pregunta
Paging suffers from external fragmentation?
Pregunta 71
Respuesta
-
is a method of memory allocation by which the program is subdivided into equal portions, or pages and core is subdivided into equal portions or blocks
-
consists of those addresses that may be generated by a processor during execution of a computation
-
is a method of allocating processor time
-
allows multiple programs to reside in separate areas of core at the time
Pregunta 72
Pregunta
What is a method of memory allocation by which the program is subdivided into equal portions, or pages and core is subdivided into equal portions or blocks?
Respuesta
-
paging
-
partition
-
segmentation
-
virtual memory
Pregunta 73
Pregunta
In memory systems, boundary registers?
Respuesta
-
track the beginning and ending of programs
-
are only necessary with unequal-length partitions
-
are only necessary with fixed partitions
-
are used for temporary program variable storage
Pregunta 74
Pregunta
A relationship between processes such that each has some part (critical section) which must not be executed while the critical section of another is being executed, is known as?
Respuesta
-
mutual exclusion
-
semaphore
-
multiprogramming
-
multitasking
Pregunta 75
Pregunta
CPU fetches the instruction from memory according to the value of?
Respuesta
-
program counter
-
status register
-
instruction register
-
program status word
Pregunta 76
Pregunta
A memory used to provide a high speed is called?
Respuesta
-
cache
-
stack pointer
-
disk buffer
-
main memory
Pregunta 77
Pregunta
Which one of the following is the address generated by CPU?
Respuesta
-
logical address
-
physical address
-
absolute address
-
none of the above
Pregunta 78
Pregunta
Runtime mapping from virtual to physical address is done by?
Respuesta
-
memory management unit
-
CPU
-
PCI
-
none of the above
Pregunta 79
Pregunta
The address of a page table in memory is pointed by:
Respuesta
-
page table base register
-
stack pointer
-
page register
-
program counter
Pregunta 80
Pregunta
Program always deals with:
Respuesta
-
logical address
-
physical address
-
absolute address
-
relative address
Pregunta 81
Pregunta
What is compaction?
Respuesta
-
a technique for overcoming external fragmentation
-
a paging technique
-
a technique for overcoming internal fragmentation
-
a technique for overcoming fatal error
Pregunta 82
Pregunta
Operating System maintains the page table for:
Respuesta
-
each process
-
each thread
-
each instruction
-
each address
Pregunta 83
Pregunta
In contiguous memory allocation:
Respuesta
-
each process is contained in a single contiguous section of memory
-
all processes are contained in a single contiguous section of memory
-
the memory space is contiguous
-
none of the above
Pregunta 84
Pregunta
When memory is divided into several fixed sized partitions, each partition may contain ________.
Pregunta 85
Pregunta
In fixed sized partition, the degree of multiprogramming is bounded by ___________.
Respuesta
-
the number of partitions
-
the CPU utilization
-
the memory size
-
all of the above
Pregunta 86
Pregunta
The first fit, best fit and worst fit are strategies to select a ______.
Respuesta
-
free hole from a set of available holes
-
process from a queue to put in memory
-
processor to run the next process
-
all of the above
Pregunta 87
Pregunta
In internal fragmentation, memory is internal to a partition and:
Respuesta
-
is not being used
-
is being used
-
is always used
-
none of the above
Pregunta 88
Pregunta
A solution to the problem of external fragmentation is:
Respuesta
-
compaction
-
larger memory space
-
smaller memory space
-
unequal size parts
Pregunta 89
Pregunta
__________ is generally faster than _________ .
Respuesta
-
first fit, best fit
-
best fit, first fit
-
worst fit, best fit
-
none of the above
Pregunta 90
Pregunta
External fragmentation exists when:
Respuesta
-
enough total memory exists to satisfy a request but it is not contiguous
-
the total memory is insufficient to satisfy a request
-
a request cannot be satisfied even when the total memory is free
-
none of the above
Pregunta 91
Pregunta
External fragmentation will not occur when:
Pregunta 92
Pregunta
When the memory allocated to a process is slightly larger than the process, then:
Pregunta 93
Pregunta
Main memory is broken into fixed-sized blocks called ________.
Respuesta
-
frames
-
pages
-
segments
-
none of the above
Pregunta 94
Pregunta
Fixed-length block of data in secondary memory is called ________.
Respuesta
-
frames
-
pages
-
segments
-
none of the above
Pregunta 95
Pregunta
Variable-length block of data that resides in secondary memory is called ________.
Respuesta
-
frames
-
pages
-
segments
-
none of the above
Pregunta 96
Pregunta
Every address generated by the CPU is divided into two parts:
Respuesta
-
page number
-
page offset
-
frame bit
-
frame offset
Pregunta 97
Pregunta
The __________ is used as an index into the page table.
Respuesta
-
page number
-
frame bit
-
page offset
-
frame offset
Pregunta 98
Pregunta
The _____ table contains the base address of each page in physical memory.
Respuesta
-
page
-
process
-
memory
-
frame
Pregunta 99
Pregunta
With paging there is no ________ fragmentation.
Respuesta
-
external
-
internal
-
either type of
-
none of the above
Pregunta 100
Pregunta
The operating system maintains a ______ table that keeps track of how many frames have been allocated, how many are there, and how many are available.
Respuesta
-
frame
-
page
-
segment
-
memory
Pregunta 101
Pregunta
For every process there is a __________.
Respuesta
-
page table
-
copy of page table
-
pointer to page table
-
frame table
Pregunta 102
Pregunta
If a page number is not found in the TLB, then it is known as a:
Respuesta
-
TLB miss
-
buffer miss
-
TLB hit
-
page fault
Pregunta 103
Pregunta
If a page table entry is present in the TLB, then it is known as a:
Respuesta
-
TLB miss
-
buffer miss
-
TLB hit
-
page fault
Pregunta 104
Pregunta
If a page table entry is not in main memory, then it is known as a:
Respuesta
-
TLB miss
-
buffer miss
-
TLB hit
-
page fault
Pregunta 105
Pregunta
When free memory is split into many unconnected pieces we call it:
Respuesta
-
Internal fragmentation
-
External fragmentation
-
Compaction
-
Memory distribution
Pregunta 106
Pregunta
Memory partitioning algorithm that uses binary tree as a data structure is called:
Respuesta
-
First-fit algorithm
-
Next-fit algorithm
-
Buddy system
-
Best-fit algorithm
Pregunta 107
Pregunta
Which of the following is not a principle of storage management responsibilities?
Pregunta 108
Pregunta
This algorithm reduces the rate of production of small gaps
Respuesta
-
Best fit
-
Worst fit
-
First fit
-
Next fit
Pregunta 109
Pregunta
This is the fastest algorithm because it searches as little as possible
Respuesta
-
Best fit
-
Worst fit
-
First fit
-
Next fit
Pregunta 110
Pregunta
This algorithm is slow, and may even tend to fill up memory with tiny useless holes
Respuesta
-
Best fit
-
Worst fit
-
First fit
-
Next fit
Pregunta 111
Pregunta
To find a free partition this algorithm starts searching from where it left off, not from the beginning
Respuesta
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Best fit
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Worst fit
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First fit
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Next fit
Pregunta 112
Pregunta
In segmentation, each address is specified by (choose two):
Respuesta
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a segment number
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an offset
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a value
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a key
Pregunta 113
Pregunta
A binary semaphore is a semaphore with integer values::A binary semaphore is a semaphore with integer values
Respuesta
-
1 and 0
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1 and -1
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0 and -1
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1 and 2
Pregunta 114
Pregunta
A monitor is a type of
Pregunta 115
Pregunta
A monitor is a type of
Pregunta 116
Respuesta
-
is a hexadecimal value
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must be accessed from only one process
-
can be accessed from multiple processes
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cannot be accessed by processes
Pregunta 117
Pregunta
A procedure defined within a ________ can access only those variables declared locally within the _______ and its formal parameters
Respuesta
-
process, semaphore
-
process, monitor
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semaphore, semaphore
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monitor, monitor
Pregunta 118
Pregunta 119
Pregunta
A set of processes is deadlock if:
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-
each process is blocked and will remain so forever
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each process is terminated
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all processes are trying to kill each other
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none of the above
Pregunta 120
Pregunta
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:
Respuesta
-
race condition
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data consistency
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starvation
-
mutual exclusion
Pregunta 121
Pregunta
An un-interruptible unit is known as
Respuesta
-
single
-
atomic
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static
-
safe
Pregunta 122
Pregunta
An un-interruptible unit is known as
Respuesta
-
atomic
-
single
-
static
-
None of the above
Pregunta 123
Pregunta
Concurrent access to shared data may result in::Concurrent access to shared data may result in
Respuesta
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data consistency
-
data insecurity
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data inconsistency
-
data complexity
Pregunta 124
Pregunta
Four necessary conditions for deadlock to exist are: mutual exclusion, no-preemption, circular wait and
Respuesta
-
hold and wait
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deadlock avoidance
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race condition
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starvation
Pregunta 125
Pregunta
If a process is executing in its critical section, then no other processes can be executing in their critical section. This condition is called
Respuesta
-
mutual exclusion
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critical exclusion
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synchronous exclusion
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asynchronous exclusion
Pregunta 126
Pregunta
If no process is suspended, the signal operation
Respuesta
-
puts the system into a deadlock state
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suspends some default process' execution
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nothing happens
-
the output is unpredictable
Pregunta 127
Pregunta
In indirect communication between processes P and Q:
Respuesta
-
there is a mailbox to help communication between P and Q
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there is another process R to handle and pass on the messages between P and Q
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there is another machine between the two processes to help communication
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none of the above
Pregunta 128
Pregunta
In the blocking send, blocking receive:
Respuesta
-
the sending process sends the message and resumes operation
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the sending process sends the message while receiver is blocked
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both sender and receiver are blocked until message is delivered
-
none of the above
Pregunta 129
Pregunta
In the non-blocking send, blocking receive:
Respuesta
-
the sending process sends the message and resumes operation
-
sender continues on, receiver is blocked until the requested message arrives
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the sending process keeps sending until it receives a message
-
none of the above
Pregunta 130
Pregunta
In the non-blocking send, non-blocking receive:
Respuesta
-
the sending process sends the message and resumes operation
-
the sending process keeps sending until the message is received
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the sending process keeps sending until it receives a message
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neither of processes are required to wait
Pregunta 131
Pregunta
In the non-blocking send:
Respuesta
-
the sending process sends the message and resumes operation
-
the sending process keeps sending until the message is received
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the sending process keeps sending until it receives a message
-
none of the above
Pregunta 132
Pregunta
Interprocess communication:
Respuesta
-
allows processes to communicate and synchronize their actions without using the same address space
-
allows processes to communicate and synchronize their actions when using the same address space
-
allows the processes to only synchronize their actions without communication
-
none of the above
Pregunta 133
Pregunta
Mutual exclusion can be provided by the
Pregunta 134
Pregunta
Mutual exclusion can be provided by the
Respuesta
-
mutex locks
-
binary semaphores
-
both
-
none of the above
Pregunta 135
Pregunta
Mutual exclusion implies that
Respuesta
-
if a process is executing in its critical section, then no other process must be executing in their critical sections
-
if a process is executing in its critical section, then other processes must be executing in their critical sections
-
if a process is executing in its critical section, then all the resources of the system must be blocked until it finishes execution
-
if a process is executing in its critical section, then all the resources of the system must be unblocked until it finishes execution
Pregunta 136
Pregunta
Mutual exclusion means that?
Respuesta
-
if a process is executing in its critical section, then no other process must be executing in their critical sections
-
if a process is executing in its critical section, then other processes must be executing in their critical sections
-
if a process is executing in its critical section, then all the resources of the system must be blocked until it finishes execution
-
None of the above
Pregunta 137
Pregunta
Part of a program where the shared memory is accessed and which should be executed invisibly, is called:
Respuesta
-
critical section
-
mutual exclusion
-
semaphores
-
directory
Pregunta 138
Pregunta
Semaphore is a/an _______ to solve the critical section problem?
Pregunta 139
Pregunta
Semaphores are mostly used to implement
Pregunta 140
Respuesta
-
synchronize critical resources to prevent deadlock
-
synchronize critical resources to prevent contention
-
are used to do I/O
-
are used for memory management
Pregunta 141
Pregunta
The bounded buffer problem is also known as
Respuesta
-
Readers - Writers problem
-
Dining - Philosophers problem
-
Producer - Consumer problem
-
Banker's algorithm
Pregunta 142
Pregunta
The code that changes the value of the semaphore is:
Pregunta 143
Pregunta
The initial value of the semaphore that allows only one of the many processes to enter their critical sections, is?
Pregunta 144
Pregunta
The link between two processes P and Q to send and receive messages is called:
Respuesta
-
communication link
-
message-passing link
-
synchronization link
-
all of the above
Pregunta 145
Pregunta
The monitor construct ensures that
Respuesta
-
only one process can be active at a time within the monitor
-
n number of processes can be active at a time within the monitor (n being greater than 1)
-
the queue has only one process in it at a time
-
all of the mentioned
Pregunta 146
Pregunta
The operations that can be invoked on a condition variable are
Respuesta
-
wait & signal
-
hold & wait
-
signal & hold
-
continue & signal
Pregunta 147
Pregunta
The process invoking the wait operation is
Respuesta
-
suspended until another process invokes the signal operation
-
waiting for another process to complete before it can itself call the signal operation
-
stopped until the next process in the queue finishes execution
-
increments the semaphore value
Pregunta 148
Pregunta
The segment of code in which the process may change common variables, update tables, write into files is known as?
Respuesta
-
critical section
-
program
-
mutual exclusion
-
non-critical section
Pregunta 149
Pregunta
The two atomic operations permissible on semaphores are
Respuesta
-
wait, signal
-
stop, start
-
hold, wait
-
wait, call
Pregunta 150
Pregunta
If the semaphore value is negative
Pregunta 151
Pregunta
two kinds of semaphores are
Respuesta
-
mutex &; counting
-
binary & counting
-
counting & decimal
-
decimal & binary
Pregunta 152
Pregunta
To avoid the race condition, the number of processes that may be simultaneously inside their critical section is
Pregunta 153
Pregunta
To enable a process to wait within the monitor
Pregunta 154
Pregunta
What is a trap/exception?
Respuesta
-
software generated interrupt caused by an error
-
hardware generated interrupt caused by an error
-
user generated interrupt caused by an error
-
failure of the system
Pregunta 155
Pregunta
When several processes access the same data concurrently and the outcome of the execution depends on the particular order in which the access takes place, is called
Respuesta
-
race condition
-
dynamic condition
-
essential condition
-
critical condition
Pregunta 156
Pregunta
Which of the following are TRUE for direct communication
Respuesta
-
A communication link can be associated with N number of process(N = max. number of processes supported by system)
-
A communication link can be associated with exactly two processes
-
Exactly N/2 links exist between each pair of processes(N = max. number of processes supported by system)
-
Exactly two link exists between each pair of processes
Pregunta 157
Pregunta
Index register, segment register, and stack register are example of:
Respuesta
-
Data registers
-
Address registers
-
Control registers
-
Status registers
Pregunta 158
Pregunta
The processor contains a single data register, called
Pregunta 159
Pregunta
This register contains the data to be written into memory or which receives the data read from memory
Respuesta
-
Memory buffer register
-
Memory address register
-
I/OAR
-
I/OBR
Pregunta 160
Pregunta
This register is used for the exchange of data between an I/O module and the processor
Respuesta
-
Memory buffer register
-
Memory address register
-
I/OAR
-
I/OBR
Pregunta 161
Pregunta
This register specifies a particular input/output device
Respuesta
-
Memory buffer register
-
Memory address register
-
I/OAR
-
I/OBR
Pregunta 162
Pregunta
This register specifies the location in memory for the next read or write
Respuesta
-
Memory buffer register
-
Memory address register
-
I/OAR
-
I/OBR
Pregunta 163
Pregunta
Which register contains condition codes set by the processor hardware as the result of operations?{
Respuesta
-
Program status word
-
Program counter
-
Stack pointer
-
Accumulator
Pregunta 164
Pregunta
Which register contains the address of the next instruction to be fetched?
Respuesta
-
Program counter
-
Instruction register
-
Execution register
-
Process counter
Pregunta 165
Pregunta
Which register contains the instruction most recently fetched?
Respuesta
-
Program counter
-
Instruction register
-
Execution register
-
Process counter
Pregunta 166
Pregunta
Control and status registers control the operation of the processor and the execution of programs
Pregunta 167
Pregunta
User-visible registers minimize main memory references by optimizing register use
Pregunta 168
Pregunta
Virtual memory takes advantage of
Respuesta
-
Fast CPU
-
Large secondary memory
-
Modular programming
-
Scheduling
Pregunta 169
Pregunta
Which of the replacement algorithms selects for replacement that page for which the time to the next reference is the longest?
Pregunta 170
Pregunta
What does process page table entry contain?
Respuesta
-
physical address of the page in secondary memory
-
virtual address of the page that is used by program
-
the frame number of corresponding page in main memory
-
size of the process
Pregunta 171
Pregunta
Which of the replacement algorithms replaces the page in memory that has not been referenced for the longest time?
Pregunta 172
Pregunta
Which of the replacement algorithms treats the page frames allocated to a process as a circular buffer?
Pregunta 173
Pregunta
What is the real address?
Respuesta
-
a physical address in main memory
-
a virtual address in main memory
-
a virtual address in secondary memory
-
a physical address in cache memory
Pregunta 174
Pregunta
What is virtual address?
Respuesta
-
The address of a storage location in virtual memory.
-
The address of a storage location in real memory.
-
The address of a storage location in cache memory.
-
The address of a storage location in main memory.
Pregunta 175
Pregunta
The size of virtual storage is limited by...
Respuesta
-
the actual number of main storage locations
-
the amount of main memory and secondary memory
-
the addressing scheme of the computer system and by the amount of secondary memory
-
the number of processors in a system
Pregunta 176
Pregunta
What is the resident set of the process?
Respuesta
-
The portion of a process that is in a secondary memory at any time.
-
The portion of a process that is actually in main memory at any time.
-
The portion of a secondary memory that contains pages or segments of particular application.
-
The set of physical addresses.
Pregunta 177
Pregunta
When does processor generate an interrupt indicating a memory access fault? {
Respuesta
-
If it encounters a logical address that is not in main memory.
-
If it encounters a logical address that is not in secondary memory.
-
If it encounters a logical address that is not in cache memory.
-
If there is no enough free memory for the running application.
Pregunta 178
Pregunta
What is trashing? {
Respuesta
-
Saving time by swapping unused pieces of process out of the memory.
-
Guessing, based on recent history, which pieces are least likely to be used in the near future.
-
Condition when the system spends most of is time swapping pieces rather than executing instructions.
-
Assumption that only a few pieces of a process will be needed over a short period of time.