Final Exam Flashcards
(123 cards)
1
Q
True or False: As a concept, virtual machines can exist outside and inside the operating system.
A
False
2
Q
True or False: We do not need hardware and software to be able to store data persistently
A
False
3
Q
Each process accesses its own private: Select one: a. Virtual machine b. Virtual source code c. Virtual address space d. Virtual client
A
Virtual address space
4
Q
Why did Linus Torvalds borrow UNIX concept, but not the code? Select one: a. Too complex b. Non-existent c. Too insecure d. Legal reasons
A
Legal reasons
5
Q
True or False: When a program runs, the primary goal is to make the system easy to use.
A
True
6
Q
Memory is just an array of bytes; to read memory, one must specify \_\_\_\_\_\_\_ to be able to access the data stored there. Select one: a. Location b. Address c. Structure d. The Byte
A
Address
7
Q
True or False: Programs are always accessing memory.
A
True
8
Q
A running program does the following: Select one: a. Executes code b. Executes instructions c. Executes commands d. Executes source code
A
Executes instructions
9
Q
To write (or update) memory, one must also specify \_\_\_\_\_\_ to be written to the given address? Select one: a. Library b. Address c. The data d. Thread
A
The data
10
Q
What other name is an OS sometimes called: Select one: a. Resource manager b. Administrator c. Executor d. Master Control Program
A
Resource manager
11
Q
True or False: PIDS are used to name processes in the UNIX O/S.
A
True
12
Q
True or False: The process list is a data structure.
A
True
13
Q
The Windows CreateProcess() system call creates a new process. What is the equivalent system call in UNIX: Select one: a. NTCreateProcess() b. process() c. fork() d. getpid()
A
fork()
14
Q
The process states include all of the following except: Select one: a. Blocked b. Stopped c. Ready d. Running
A
stopped
15
Q
What technique uses the OS to create an illusion by virtualizing the CPU and running one process, then stopping it and running another? Select one: a. Virtualization b. Context switch c. Scheduling d. Time sharing
A
Time sharing
16
Q
What system call is used to send signals to a process, including directives to go to sleep, or die: Select one: a. API b. fork() c. kill () d. wait ()
A
kill()
17
Q
A parent can be made to wait for a child process to finish what it has been doing by which command? Select one: a. PID b. Hello World c. Prompt > d. wait() system call
A
wait() system call
18
Q
In early (or simple) operating systems, the loading process is done: Select one: a. One at a time b. Eagerly c. In groups d. At compile time
A
Eagerly
19
Q
True or False: The natural counterpart of time sharing is space sharing, where a resource is divided (in space) among those who wish to use it.
A
True
20
Q
Which of the following statements is incorrect?
Select one:
a. An operating system provides an environment for the execution of programs.
b. An operating system manages system resources.
c. Operating systems provide both command line as well as graphical user interfaces.
d. Operating systems must provide both protection and security.
A
Operating systems provide both command line as well as graphical user interfaces.
21
Q
True or False: The shell is just a user program.
A
True
22
Q
A process may transition to the Ready state by which of the following actions? Select one: a. Completion of an I/O event b. Awaiting its turn on the CPU c. Newly-admitted process d. All of the above
A
All of the above
23
Q
All of the following are Machine States except: Select one: a. Address space b. Registers c. Memory d. API
A
API
24
Q
This system call is useful when you want to run a program that is different from the calling program: Select one: a. API b. fork() c. exec() System Call d. wait ()
A
exec() System Call
25
```
_____ provide(s) an interface to the services provided by an operating system.
Select one:
a. Shared memory
b. System calls
c. Simulators
d. Communication
```
System calls
26
True or False: Application programmers typically use an API rather than directory invoking system calls.
True
27
True or False: A running program is not a process.
False
28
True or False: The register context will not hold the contents of its registers.
False
29
True or False: UNIX pipes are implemented with the execvp() system call. This is where the output of one process seamlessly is used as input to the next, and long and useful chains of commands can be strung together.
False
30
True or False: MenuMeters (from Raging Menace software) runs on our PC toolbars.
False
31
True or False: Address space can be shared or dedicated to users.
True
32
```
If a programmer prints out the address of a program its always?
Select one:
a. Physical
b. Combination
c. Virtual
d. Single
```
Virtual
33
True or False: A dual-core system requires each core has its own cache memory.
False
34
```
What is a fundamental problem of MQMS:
Select one:
a. Scalability
b. Locking
c. Load Imbalance
d. Migration
```
Load Imbalance
35
True or False: Multithreaded applications can spread work across multiple CPUs and thus run faster when given more CPU resources.
True
36
True or False: The multiple-queue approach (MQMS) scales better than the single-queue approach (SQMS).
True
37
True or False: Adding more CPUs will make a single application run faster.
False
38
True or False: Multicore processors contain one CPU cores on a single chip.
False
39
```
The fundamental difference between single-CPU hardware and multi-CPU hardware?
Select one:
a. Temporal Locality
b. Spatial Locality
c. Caches
d. Time sharing
```
Caches
40
True or False: Interactivity refers to single users on the same system
False
41
True or False: Cache coherency involves ensuring that multiple caches store the most updated version of the stored data.
True
42
True or False: If you have a single CPU, hardware caches will help the processor run programs faster.
True
43
Putting all jobs that need to be scheduled into a single queue is called:
Select one:
a. Single queue multiprocessor scheduling
b. Single queue multilocking scheduling
c. Single queue multi scheduling
d. None of the Above
Single queue multiprocessor scheduling
44
```
__________ is when each cache pays attention to memory updates by observing the bus that connects them to main memory. When a CPU then sees an update for a data item it holds in its cache, it will notice the change and either invalidate its copy or update it.
Select one:
a. Cache Coherence
b. Bus Snooping
c. Lock-free
d. Locality
```
Bus Snooping
45
```
The address can be used by all of the following except:
Select one:
a. Heap
b. Program code
c. Registers
d. None
```
Registers
46
```
Cache Affinity means run process on:
Select one:
a. Same CPU
b. Different CPU
c. Multiple CPU’s
d. One CPU
```
Same CPU
47
Which of the following statements are false with regards to the Linux CFS scheduler?
Select one:
a. Each task is assigned a proportion of CPU processing time.
b. Lower numeric values indicate higher relative priorities.
c. There is a single, system-wide value of vruntime.
d. The scheduler doesn't directly assign priorities.
There is a single, system-wide value of vruntime.
48
```
What technique is used to prevent threads from removing the same head element?
Select one:
a. Locking
b. Threading
c. Mutex
d. Sychronization
```
Locking
49
```
Load imbalance can be handled by:
Select one:
a. Multiple queues
b. Multiple CPUs
c. Migration
d. Work stealing
```
Migration
50
```
Which is not a goal of virtual memory (VM)?
Select one:
a. Protect
b. Efficient
c. Transparent
d. Isolation
```
Isolation
51
```
A(n) ______ matches the process with each entry in the TLB.
Select one:
a. address-space identifier
b. process id
c. stack
d. page number
```
address-space identifier
52
```
With segmentation, a logical address consists of _____.
Select one:
a. segment number and offset
b. segment name and offset
c. segment number and page number
d. segment table and segment number
```
segment number and offset
53
Segment Base Size
Code 32k 2k
Heap 34k 2k
Stack 28k 2k
True or False: calloc() allocates memory and also zeroes it before returning.
True
54
True or False: The stack has been relocated to physical address 28KB in the diagram, but with one important difference: it grows forward in physical memory.
False
55
True or False: A base register is used to transform physical addresses (generated by the program) into virtual addresses.
False
56
```
_______ occurs when you forget to free memory.
Select one:
a. Memory leak
b. Memory loss
c. Memory block
d. None of the above
```
Memory leak
57
Internal fragmentation means:
Select one:
a. Space inside the allocated unit is not all used but fragmented
b. Space inside the allocated unit is unfragmented
c. Space inside the allocated unit is all used but fragmented
d. Space inside the allocated unit is not unfragmented
Space inside the allocated unit is not all used but fragmented
58
```
When free space gets chopped into little pieces of different sizes and is thus fragmented.
Select one:
a. Splitting
b. Internal fragmentation
c. Coalescing
d. External fragmentation
```
External fragmentation
59
```
Consider a 32-bit address for a two-level paging system with an 8 KB page size. The outer page table has 1024 entries. How many bits are used to represent the second level page table?
Select one:
a. 10
b. 8
c. 12
d. 9
```
9
60
The data structure free list is used to track?
Select one:
a. Ranges of the virtual memory which is not currently in use
b. Ranges of the physical memory which is currently in use
c. Ranges of the physical memory which is not currently in use
d. Ranges of the virtual memory which is currently in use
Ranges of the physical memory which is not currently in use
61
Which is not a common error?
Select one:
a. Freeing memory before you are done with it
b. Forgetting to initialize allocated memory
c. Forgetting to allocate memory
d. All are common errors
All are common errors
62
```
Which of the following data structures is appropriate for placing into its own segment?
Select one:
a. heap
b. kernel code and data
c. user code and data
d. all of the above
```
all of the above
63
```
Given the logical address 0xAEF9 (in hexadecimal) with a page size of 256 bytes, what is the page offset?
Select one:
a. 0xAE
b. 0xF9
c. 0xA
d. 0xF900
```
0xF9
64
Which of the following techniques are correct for physical address?
Select one:
a. Physical address = virtual address + translation
b. Physical address = virtual address + bounds
c. Physical address = virtual address + limits
d. Physical address = virtual address + base
Physical address = virtual address + base
65
```
To save memory, sometimes it is useful to share certain memory segments between address spaces. This is called:
Select one:
a. Code swapping
b. Code sharing
c. Address sharing
d. Address swapping
```
Code sharing
66
```
Assume the value of the base and limit registers are 1200 and 350 respectively. Which of the following addresses is legal?
Select one:
a. 355
b. 1200
c. 1551
d. all of the above
```
1200
67
```
What is used to free heap memory no longer in use.
Select one:
a. The malloc() Call
b. Stack
c. The free() Call
d. Automatic
```
The free() Call
68
These instructions will store the value of eax to at the end of the program:
128: movl 0x0(%ebx), %eax ;load 0+ebx into eax
132: addl $0x03, %eax ;add 3 to eax register
135: movl %eax, 0x0(%ebx) ;store eax back to mem
Select one:
a. Different memory location
b. Multiple locations
c. Same memory location
d. One location
Same memory location
69
```
Basic strategies to memory allocates does not include:
Select one:
a. Worst Fit
b. Last Fit
c. Best Fit
d. First Fit
```
Last Fit
70
True or False: A base register is used to transform physical addresses (generated by the program) into virtual addresses.
False
71
```
Which algorithm is considered reasonable for managing a buffer cache?
Select one:
a. least-recently-used (LRU)
b. first-in-first-out (FIFO)
c. most-recently-used
d. least-frequently-used (LFU)
```
least-recently-used (LRU)
72
True or False: A dual-core system requires each core has its own cache memory.
False
73
```
Segment Base
Size
Code 32K
2K
Heap 34K
2K
Stack 28K
2K
```
Figure 16.3: Segment Register Values
True or False: The stack has been relocated to physical address 28KB in the diagram above, but with one important difference: it grows forward in physical memory
False
74
```
_____ is not a technique for passing parameters from an application to a system call
Select one:
a. Cache memory
b. Registers
c. Stack
d. Special block in memory
```
Cache memory
75
True or False: The page selection policy only determines which page to swap not when to swap pages.
False
76
True or False: The page-replacement policy means that pages are not placed to make more space.
False
77
```
Swap space is used for:
Select one:
a. Memory overlays
b. Stack overflows
c. Swapping pages
d. Saving space on hard disk drives
```
Swapping pages
78
```
Two important design issues for cache memory are ____
Select one:
a. speed and volatility.
b. size and replacement policy.
c. power consumption and reusability.
d. size and access privileges.
```
size and replacement policy
79
Optimal page replacement ____.
Select one:
a. is the page-replacement algorithm most often implemented
b. is used mostly for comparison with other page-replacement schemes
c. can suffer from Belady's anomaly
d. requires that the system keep track of previously used pages
is used mostly for comparison with other page-replacement schemes
80
```
Using the LRU policy which page will be evicted first?
Access Hit/Miss? Evict Cache State
0 Miss LRU! 0
1 Miss LRU! 0, 1
2 Miss LRU! 0, 1, 2
0 Hit LRU! 1, 2, 0
1 Hit LRU! 2, 0, 1
3 Miss 2 LRU! 0, 1, 3
0 Hit LRU! 1, 3, 0
3 Hit LRU! 1, 0, 3
1 Hit LRU! 0, 3, 1
2 Miss 0 LRU! 3, 1, 2
1 Hit LRU! 3, 2, 1
```
Select one:
a. 2 Miss LRU! 0, 1, 2
b. 3 Miss 2 LRU! 0, 1, 3
c. 3 Hit LRU! 1, 0, 3
d. 1 Hit LRU! 3, 2, 1
3 Miss 2 LRU! 0, 1, 3
Chociaż wydaje mi sie ze jest 1 Hit LRU! 3, 2, 1
81
Swap space management ____.
Select one:
a. is a high-level operating system task
b. tries to provide the best throughput for the virtual memory system
c. is primarily used to increase the reliability of data in a system
d. None of the above
tries to provide the best throughput for the virtual memory system
82
Which of the following is not a reason explaining why mobile devices generally do not support swapping?
Select one:
a. Limited space constraints of flash memory.
b. Small size of mobile applications do not require use of swap space
c. Limited number of writes of flash memory.
d. Poor throughput between main memory and flash memory
Small size of mobile applications do not require use of swap space
83
```
Given the reference string of page accesses: 1 2 3 4 2 3 4 1 2 1 1 3 1 4 and a system with three page frames, what is the final configuration of the three frames after the LRU algorithm is applied?
Select one:
a. 1, 3, 4
b. 3, 1, 4
c. 4, 1, 2
d. 1, 2, 3
```
3, 1, 4
84
```
In figure 20.1 which block is the next free space for allocation?
Select one:
a. Block 3
b. PFN 0
c. PFN 3
d. Block 2
```
Block 2
| The only free one
85
```
_____ is the algorithm implemented on most systems.
Select one:
a. FIFO
b. Least frequently used
c. Most frequently used
d. LRU
```
LRU
86
```
Using the FIFO policy which page will be evicted first?
Access Hit/Miss? Evict Cache State
0 Miss First-in! 0
1 Miss First-in! 0, 1
2 Miss First-in! 0, 1, 2
0 Hit First-in! 0, 1, 2
1 Hit First-in! 0, 1, 2
3 Miss 0 First-in! 1, 2, 3
0 Miss 1 First-in! 2, 3, 0
3 Hit First-in! 2, 3, 0
1 Miss 2 First-in! 3, 0, 1
2 Miss 3 First-in! 0, 1, 2
1 Hit First-in! 0, 1, 2
Select one:
a. 1 Miss 2 First-in! 3, 0, 1
b. 2 Miss 3 First-in! 0, 1, 2
c. 3 Miss 0 First-in! 1, 2, 3
d. 0 Miss 1 First-in! 2, 3, 0
```
3 Miss 0 First-in! 1, 2, 3
87
```
What happens if line number 2 is false and 3 is true?
PFN = FindFreePhysicalPage()
2 if (PFN == -1) // no free page found
3 PFN = EvictPage() // run replacement algorithm
4 DiskRead(PTE.DiskAddr, pfn) // sleep (waiting for I/O)
5 PTE.present = True // update page table with present
6 PTE.PFN = PFN // bit and translation (PFN)
```
Select one:
a. Check for any free pages
b. Check for free space
c. Will not page in desired pages
d. Page in desired page
Page in desired page
88
The OS decides which page (or pages) to evict from memory by following some general principles, which is not?
Select one:
a. Ranges of the virtual memory which is not currently in use
b. Using History: LRU
c. Average memory access time (AMAT)
d. Cache Management
Average memory access time (AMAT)
89
Which of the following statements is false?
Select one:
a. Swapping works in conjunction with virtual memory techniques.
b. Some systems allow for multiple swap spaces (disks).
c. Solaris only swaps pages of anonymous memory.
d. Typically, entire processes are swapped into memory.
Typically, entire processes are swapped into memory.
90
```
Channel logging tokens can be set to all but:
Select one:
a. Relaxed
b. Strict
c. Both versions
d. None
```
Both versions
91
```
Computers not joined to the domain can use event forwarding in conjunction with:
Select one:
a. HTTP
b. WinRM
c. HTTPS
d. SSL/TLS
```
SSL/TLS
92
True or False: Collected events are almost always malicious.
False
93
True or False: The Windows operating system has a built-in network based firewall.
False
94
```
For Windows Defender event ID 3002 means?
Select one:
a. Action on malware failed
b. Failed to update signatures
c. Real time protection failed
d. Unexpected error
```
Real time protection failed
95
True or False: Mobile devices create a log whenever they enter and leave a wireless network.
True
96
True or False: The event log file is set to 1G of storage and one should overwrite it rather than allocate more space or start a new log file of 1G.
False
97
```
This command “winrm id –remote:TARGET” will:
Select one:
a. Locates TARGET Machine
b. Enumerate all listeners
c. Identifies remote machine TARGET
d. Identifies TARGET machine
```
Identifies remote machine TARGET
98
```
When troubleshooting the target machine the local host name should be set to:
Select one:
a. Local host
b. Remote:
c. TARGET
d. Local machine
```
TARGET
99
```
In the process of application whitelisting events are collected for all except:
Select one:
a. Application whitelisting
b. Applocker
c. Blocked applications
d. EMET
```
EMET
100
The following are all assumptions about processes except:
Select one:
a. Each job runs for the same amount of time
b. All jobs arrive at the same time
c. All jobs only use the CPU (i.e., they perform no I/O)
d. The run-time of each job is not known
The run-time of each job is not known
101
```
Return-from-trap instruction returns into the calling user program while simultaneously reducing the privilege level back to ________
Select one:
a. User mode
b. Kernel mode
c. OS mode
d. CPU mode
```
User mode
102
Basic algorithm for scheduling include all but:
Select one:
a. Shortest Time-to-Completion Last (STCL)
b. First Come, First Served (FCFS)
c. Shortest Job First (SJF)
d. First Out (FIFO)
Shortest Time-to-Completion Last (STCL)
103
```
Allows the kernel to carefully expose certain key pieces of functionality to user programs?
Select one:
a. user mode
b. system call
c. kernel mode
d. trap
```
system call
104
True or False: The process list a data structure.
True
105
True or False: Direct execution refers to running a program directly on the CPU.
True
106
```
The _____ scheduler allocates available memory to each process using a percentage.
Select one:
a. Equal
b. Global
c. Fair-Share
d. Slab
```
Fair-Share
107
True or False: Ticket inflation is when a process can temporarily only raise the number of tickets it owns.
False
108
True or False: Timesharing means the operating system shares the physical CPU among many jobs running one at a time.
True
109
Basic algorithms for scheduling include all but:
Select one:
a. Shortest Time-to-Completion Last (STCL)
b. First Come, First Served (FCFS)
c. Shortest Job First (SJF)
d. First Out (FIFO)
Shortest Time-to-Completion Last (STCL)
110
True or False: Turnaround time is defined as is the total time taken between the submission of a program/process/thread/task for execution and the return of the complete output to the customer/user.
True
111
Processes running in the system are sometimes called workload
True/False
True
112
True or False: Turnaround time is defined as the time at which the job finally completes minus the time at which the job arrived in the system.
Tturnaround = Tcompletion - Tarrival
True
113
The term random-access memory or RAM means that:
Select one:
a. Memory is dynamically accessed Incorrect
b. Memory is randomly accessed
c. RAM is hard to gauge
d. Memory is not random
Memory is randomly accessed
114
True or False: Internal fragmentation happens when big pages waste space within each page.
True
115
True or False: Paging introduces a problem that page tables are too big and thus consume too much memory
True
116
```
Single larger pages of 4 MB or more are commonly used for applications such as:
Select one:
a. Programs
b. Memory management systems
c. Data base systems
d. Reserachers
```
Data base systems
117
Virtual page numbers and page off sets are used to:
Select one:
a. Track RAM usage
b. Store memory values
c. Translate virtual addresses to physical memory addresses
d. Store RAM values
Translate virtual addresses to physical memory addresses
118
True or False: Implementing paging support without care will lead to a faster machine.
False
119
```
Consult the following figure; which page frame will be used first?
Select one:
a. Page frame 1
b. Page frame 2
c. Page frame 3
d. Page frame 4
```
Page frame 3
120
True or False: A 32-bit logical address with 8 KB page size will have 1,000,000 entries in a conventional page table?
False
121
True or False: There are usually two types of locality, temporal and spatial
True
122
True or False: Fragmentation does not occur in a paging system.
False
123
True or False: The Event Viewer allows users to create custom views that organize event data based on a custom filter.
True
