151. The segment of code in which the process may change common variables, update tables, write into files is known as?
● critical section
● mutual exclusion
● non-critical section
● program
152. Mutual exclusion means that?
● none of the above
● 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 all the resources of the system must be blocked until it finishes exclusion
● if a process is executing in its critical section, then other processes must be executing in their critical section
153. A minimum of _____ variable(четыре вопроса в одном)s) is/are required to be shared between processes to solve the critical section problem?
● four
● one
● three
● two
154. An un-interruptible unit is known as:
● atomic
● static
● single
155. Semaphore is a/an _______ to solve the critical section problem?
● hardware for a system
● integer variable
● complex structure
● special program for a system
156. The two atomic operations permissible on semaphores are:
● stop
● hold
● signal
● wait
157. The code that changes the value of the semaphore is:
● critical section code
● remainder section code
● non-critical section code
158. The two kinds of semaphores are:
● decimal
● binary, counting
● mutex
159. A binary semaphore is a semaphore with integer values :
● 0.5
● 0
● -1
● 1
160. A monitor is a type of:
● semaphore
● low level synchronization construct
● high level synchronization construct
161. What is the reusable resource:
● that can be shared between various threads
● that can be used by one process at a time and is not depleted by that use
● that can be used by more than one process at a time
162. Which of the following condition is required for deadlock to be possible?
● a process may hold allocated resources while awaiting assignment of other resources
● no resource can be forcibly removed from a process holding it
● all of the above
163. A system is in the safe state if:
● both a and b
● b) there exist a safe sequence
● a) the system can allocate resources to each process in some order and still avoid a deadlock
164. Which one of the following is the deadlock avoidance algorithm?
● round-robin algorithm
● banker’s algorithm
● elevator algorithm
● dining philosophers problem
165. A problem encountered in multitasking when a process is perpetually denied necessary resources is called:
● inversion
● aging
● deadlock
● starvation
166. The number of resources requested by a process:
● must always be less than the total number of resources available in the system
● must not exceed the total number of resources available in the system
● must always be equal to the total number of resources available in the system
● must exceed the total number of resources available in the system
167. For non-sharable resources like a printer, mutual exclusion:
● may exist
● must not exist
● must exist
168. A deadlock avoidance algorithm dynamically examines the __________, to ensure that a circular wait condition can never exist.
● system storage state
● resource allocation state
● operating system
● resources
169. A state is safe, if:
● the state keeps the system protected and safe
● the system does not crash due to deadlock occurrence
● the system can allocate resources to each process in some order and still avoid deadlock
170. The available vector defines
● total amount of each resource NOT allocated to any process
● total amount of each resource allocated to all processes
● total amount of each resource in the system
● total amount of resources required for all processes
171. The resource vector define
172. This matrix defines the current allocation to process i of the resource j
● Claim matrix
● Request matrix
● Resource matrix
● Allocation matrix
173. This matrix defines the amount of resources of type j requested by process i
174. This matrix defines requirements of processes i for the resources j
175. The banker's algorithm is referred to as
● resource allocation refusal
● loan allocation denial
● resource allocation denial
● denial of service
176. 'Hold and wait' condition for deadlock is defined as
● Each process holds resource needed by next process in chain
● Process holds a resource while awaiting for other resource
● No resource can be forcibly removed from process holding it
● Only one process may use a resource at a time
177. 'Circular wait' condition for deadlock is defined as
178. 'No preemption' condition for deadlock is defined as
179. 'Mutual exclusion' condition for deadlock is defined as
180. What is NOT an example of consumable resource?
● Messages
● Main memory
● Signals
● Information in I\O buffers
181. What is NOT an example of reusable resource?
● i/o channels
● interrupt
● processors
● semaphores
182. This resource can be created and destroyed
● finite resource
● consumable resource
● restartable resource
● resumable resource
183. This resource can be safely used by only one process at a time and is not depleted by that use
● refreshing resource
● reusable resource
● replenishing resource
● refurbished resource
184. Deadlock inevitable region can be referred to as a
● false region
● final region
● fatal region
● fun region
185. This illustrates the progress of two processes competing for two resources
● joint progress diagram
● joint regress diagram
● joint ingres diagram
● joint process diagram
186. When each process in the set is blocked awaiting for resource siezed by another blocked process
● it is a mortallock
● it is a softlock
● it is a deadlock
● it is a deadend
187. Which of the following statements is false:
● 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
● the system must stop everything while it performs the compaction
● compaction is also known as garbage collection
● the technique of storage compaction involves moving all occupied areas of storage to one end or other of main storage
● compaction does not involve relocation of programs
188. Memory is:
● is typically characterized by interactive processing and time-slicing of the CPU’s time to allow quick response to each user
● is a device that performs a sequence of operations specified by instructions in memory
● is a sequence of the instructions
● is the device where information stored
189. Processor is:
190. Program is:
191. The memory allocation scheme subject to "external" fragmentation is?
● pure demand paging
● multiple contiguous fixed partitionings
● swapping
● segmentation
192. The memory allocation scheme subject to "internal" fragmentation is?
193. Any program, no matter how small, will occupy an entire partition results in?
● external fragmentation
● paging
● internal fragmentation
194. How to solve problem of equal-size partitions? swapping (?) ----- page 318 book
● virtual memory segmentation
● compaction
● unequal-size partitions
195. How to solve problem of "external" fragmentation?
● none of these
● smaller memory space
● larger memory space
196. A page fault?
● is an error is a specific page
● is an access to a page not currently in memory
● is a reference to a page belonging to another program
● occurs when a program accesses a page of memory
197. Which of the following statements is false?
198. Swapping:
● does not work with overlaying
● allows each program in turn to use the memory
● allows many programs to use memory simultaneously
199. Which of the following is not true about the memory management?
● None of the above
● segmented memory can be paged
● paging suffers from internal fragmentation
● segmentation suffers from external fragmentation
● virtual memory is used only in multi-user systems
200. True or false: segmentation suffers from external fragmentation?
False
True
201. True or false: paging suffers from external fragmentation?
202. 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?
● partition
● virtual memory
203. In memory systems, boundary registers?
● are used for temporary program variable storage
● are only necessary with fixed partitions
● track page boundaries
● track the beginning and ending of programs
204. A relationship between processes such that each has some part (четыре вопроса в одном)critical section) which must not be executed while the critical section of another is being executed, is known as?
● multiprogramming
● Mutual exclusion
● Semaphore
● Multitasking
205. CPU fetches the instruction from memory according to the value of?
● program status word
● instruction register
● program counter
● status register
206. A memory used to provide a high speed is called?
● stack pointer
● disk buffer
● main memory
● cache
207. Which one of the following is the address generated by CPU?
● absolute address
● physical address
● logical address
208. Runtime mapping from virtual to physical address is done by?
● PCI
● memory management unit
● CPU
209. The address of a page table in memory is pointed by:
● page register
● page table base register
210. Program always deals with:
● relative address
211. What is compaction?
● a technique for overcoming external fragmentation
● a technique for overcoming internal fragmentation
● a technique for overcoming fatal error
● a paging technique
212. Operating System maintains the page table for:
● each address
● each instruction
● each thread
● each process
213. In contiguous memory allocation:
● all processes is contained in a single contiguous section of memory
● the memory space is contiguous
● each process is contained in a single contiguous section of memory
214. When memory is divided into several fixed sized partitions, each partition may contain ________.
● multiple processes at once
● at least one process
● exactly one process
215. In fixed sized partition, the degree of multiprogramming is bounded by ___________.
● the CPU utilization
● the number of partitions
● the memory size
216. The first fit, best fit and worst fit are strategies to select a ______.
● processor to run the next process
● free hole from a set of available holes
● process from a queue to put in memory
217. In internal fragmentation, memory is internal to a partition and:
● is being used
● is always used
● is not being used
218. A solution to the problem of external fragmentation is:
● unequal size parts
● larger memory size
219. __________ is generally faster than _________ .
● first fit, best fit
● best fit, first fit
● worst fit, best fit
220. External fragmentation exists when:
● a request cannot be satisfied even when the total memory is free
● enough total memory exists to satisfy a request but it is not contiguous
● the total memory is insufficient to satisfy a request
221. External fragmentation will not occur when:
● next fit is used
● best fit is used
● first fit is used
● no matter which algorithm is used, it will always occur
222. When the memory allocated to a process is slightly larger than the process, then:
● internal fragmentation occurs
● external fragmentation occurs
● both will occur
223. Main memory is broken into fixed-sized blocks called ________.:
● segments
● frames
● pages
224. Fixed-length block of data in secondary memory is called ________.:
segments
225. Variable-length block of data that resides in secondary memory is called ________.
226. Every address generated by the CPU is divided into two parts:
● page offset
● frame bit
● page number
● frame offset
