227. The __________ is used as an index into the page table.
● frame bit
● frame offset
● page offset
● page number
228. The _____ table contains the base address of each page in physical memory.
● frame
● page
● memory
● process
229. With paging there is no ________ fragmentation.
● internal
● external
● none of the above
● either type of
230. 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.
● segment
231. For every process there is a __________.
● page table
● frame table
● copy of page table
● pointer to page table
232. If a page number is not found in the TLB, then it is known as a:
● TLB ht
● buffer miss
● TLB miss
233. If a page table entry is present in the TLB, then it is known as a:
● TLB hit
● page fault
234. If a page table entry is not in main memory, then it is known as a:
235. In segmentation, each address is specified by (четыре вопроса в одном)choose two):
● a key
● a value
● a segment number, an offset
236. The set-associative map technique is a combination of the direct and associative technique
true
false
237. The spatial aspect of the locally of reference means ________
d. That the recently executed instruction is executed again next
c. That the instruction executed will be executed at a later time
b. That the recently executed won’t be executed again
a. That the instruction in close proximity of the instruction executed will be executed in future
238. The technique of searching for a block by going through all the tags is ______
d. Binary search
c. indirect search
b. Associative search
a. Linear search
239. The memory blocks are mapped on to the cache with the help of _________
d. Write policy
c. Replacement policy
b. Mapping functions
a. Hash functions
240. For 4 page frames, the following is the reference string: 1 2 3 4 2 1 5 6 2 1 2 3 7 6 3 2 1 2 3 6 How many page faults does the LRU page replacement algorithm produce(четыре вопроса в одном)including page faults when the frames were free)?
d. 8
c. 12
b. 14
a. 10
241. Consider a logical address space of 32 pages with 512 words per page, mapped onto a physical memory of 16 frames. How many bits are required in the physical address?
d. 14
b. 15
a. 13
242. Assuming a 1-KB page size, for the following address reference(четыре вопроса в одном)provided as decimal number) 256, what is the page number?
0
-2
2
243. At a particular time of computation the value of a counting semaphore is 7. Then 20P operations were completed on this semaphore. The resulting value of the semaphore is
d. 2
c. 42
b. 12
a. 7
244. If it is not possibl e to tell, by looking at the program, what will happen when it executes, then the program is
d. non-distributed
c. non-deterministic
b. non-deadlocked
a. non-divisible
245. The program follows to use a shared binary semaphore T: Process A int Y; A1: Y=X*2; A2: X=Y; signal(четыре вопроса в одном)T); Process B int Z; B1:wait(четыре вопроса в одном)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?
d. three
c. four
b. one
a. two
246. Computer programmers are often concerned with synchronization constraints, which are requirements pertaining to the order of events. They are:
d. Serialization and Mutual exclusion
c. Queueing and dispatching
b. Scheduling and dispatching
a. Serialization and Mutual inclusion
247. The effectiveness of the cache memory is based on the property of ______
d. Locality of reference
c. Memory localisation
b. Memory size
a. Memory access time
248. In direct mapping the presence of the block in memory is checked with the help of _______ field.
d. ser
c. tag
b. block
a. word
249. This matrix gives the maximum requirement of each process for each resource
d. Allocation matrix
c. Claim matrix
b. Resources matrix
a. Available matrix
250. If the resource allocation graph contains a cycle
d. then a deadlock does not exist
c. then the system is in a safe state
b. either deadlock exists or system is in a safe state
a. then a deadlock exists
251. Segment replacement algorithms are more complex than page replacement algorithms because
d. Segments are better than pages
c. Pages are better than segments
b. Segments have variable sizes
a. Segments have fixed size
252. When does processor generate an Interrupt indicating a memory access fault?
d. If there is no enough free memory for the running application
c. If it encounters a logical address that is not in main memory
b. If it encounters a logical address that is not in cache memory
a. If it encounters a logical address that is not in secondary memory
253. Which of the replacement algorithms selects for replacement that page for which the time to the next reference is the longest?
d. LRU
c. Clock
b. optimal
a. FIFO
254. Given five memory partitions of 100KB, 500KB, 200KB, 300KB, and 600KB. The first-fit algorithm places processes of 212KB, 417KB, 112KB, and 426KB. In whch partition 426KB is placed?
f. 300KB
e. 100KB
d. 500KB
c. 200KB
b. 600KB
a. No sufficient amount
255. Given five memory partitions of 100KB, 500KB, 200KB, 300KB, and 600KB. The worst-fit algorithm places processes of 212KB, 417KB, 112KB, and 426KB. In whch partition 426KB is placed?
d. 200KB
c. 600KB
b. No sufficient amount
a. 500KB
256. For 4 page frames, the following is the reference string: 1 2 3 4 2 1 5 6 2 1 2 3 7 6 3 2 1 2 3 6 How many page faults does the Optimal page replacement algorithm produce (четыре вопроса в одном)including page faults when the frames were tree)?
d. 12
c. 10
b. 8
a. 14
257. A computer system has 6 tape drives, with ‘n’ processes competing for them. Each process may need 3 tape drives. The maximum value of ‘n’ for which the system is guaranteed to be deadlock free is
c. 1
b. 3
a. 4
258. A system has 3 processes sharing 4 resources. If each process needs a maximum of 2 units then
d. deadlock can never occur
c. they all will starve
b. deadlock must occur
a. deadlock may occur
259. The two kinds of semaphore are
d. counting & decimal
c. mutex & counting
b. decimal & binary
a. binary & counting
260. The size of a process is limited to the size of
d. secondary storage
c. physical memory
b. external storage
a. none of the mentioned
261. In FIFO page replacement algorithm, when a page must be replaced
d. none of the mentioned
c. newest page is chosen
b. oldest page is chosen
a. random page is chosen
262. For larger page tables, they are kept in main memory and a ______ points to the page table
d. page table register pointer
c. page table base
b. page table base pointer
a. page table base register
263. The essential content(s) in each entry of a page table is/are
d. Page frame number
c. Both virtual page number and page frame number
b. Access right information
a. Virtual page number
264. When a program tries to access a page that is mapped in address space but not loaded in physical memory, then
d. fatal error occurs
c. segmentation fault occurs
b. page fault occurs
a. no error occurs
265. A page fault occurs when
d. a page gives inconsistent data
c. a page is invisible
b. a page cannot be accessed due to its absence from memory
a. all of the mentioned
266. sem.wait()
d. decrements the semaphore
c. reads the semaphore
b. initializes the semaphore
a. increments the semaphore
267. Each entry in a segment table has a
d. segment base
c. segment peak
b. segment value
268. Virtual memory takes advantage of
d. Scheduling
c. Modular programming
b. Large secondary memory
a. Fast CPU
269. Because of virtual memory, the memory can be shared among
d. processes
c. threads
b. none of the mentioned
a. instructions
270. If no frames are free and modify bit is set for all pages in frames, _____ page transfer(s) is/are required
d. one
b. three
271. Which is the fastest cache mapping function?
c. Set associative mapping
b. Direct mapping
a. Fully associative mapping
272. This bit indicates if the slot holds a block belonging to the program being executed
d. Dirty bit
c. Valid bit
b. Control bit
a. Reference bit
273. The size of virtual storage is limited by….
i. The set of physical addresses
g. the amount of main memory and secondary memory
f. The portion of a process that is in a secondary memory at any time
e. the actual number of main storage locations
d. The portion of a secondary memory that contains pages or segments of particular application
c. the number of processors in a system
b. The portion of a process that is actually in mean memory at any time
a. the addressing scheme of the computer system and by the amount of secondary memory
274. Optimal page - replacement algorithm is difficult to implement, because
d. it is too complex
c. it requires future knowledge of the reference string
b. it is extremely expensive
a. it requires a lot of information
276. 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:
d. dynamic condition
c. critical condition
b. essential condition
a. race condition
277. Given five memory partitions of 100KB, 500KB, 200KB, 300KB, and 600KB. The bestfit algorithm places processes of 212KB, 417KB, 112KB, and 426KB. In whch partition 112KB is placed?
f. No sufficient amount
e. 300KB
d. 100KB
c. 500KB
b. 200KB
a. 600KB
278. Address Binding is
d. binding two addresses together to form a new address in a different memory space
c. locating an address with the help of another address
b. a mapping from one address space to another
a. going to an address in memory
279. When free memory is split into many unconnected pieces we call it:
d. Compaction
c. Internal fragmentation
b. External fragmentation
a. Memory distribution
280. If the size of logical address space is 2 to the power of m, and a page size is 2 to the power of n addressing units, then the high order _____ bits of a logical address designate the page number, and the ____ low order bits designate the page offset
d. m, n
c. m - n, n
b. n, m
a. m - n, m
281. Assuming a 1-KB page size, for the following address reference(четыре вопроса в одном)provided as decimal number) 2375, what is the page number?
1
3
282. A system has 12 magnetic tape drives and 3 processes: P0, P1, and P2. Process P0 requires 10 tape drives, P1 requires 4 and P2 requires 9 tape drives. Process Maximum needs Currently allocated P0 10 5 P1 4 2 P2 9 2 Which of the following sequence is a safe sequence?
d. P0, P1, P2
c. P2, P0, P1
b. P1, P0, P2
a. P1, P2, P0
283. If there are 32 segments, each of size 1KB, then the logical address should have
d. 15 bits
c. 16 bits
b. 14 bits
a. 13 bits
284. A multilevel page table is preferred in comparison to a single level page table for translating virtual address to physical address because
d. it helps to reduce the size of page table needed to implement the virtual address space of a process
c. it reduces the memory access time to read or write a memory location
b. it is required by the translation lookaside buffer
a. It helps to reduce the number of page faults in page replacement algorithms
285. If the resources are always preempted from the same process, _______ can occur
d. aging
c. system cash
b. starvation Problems
a. deadlock
286. Which one of the following is a visual (mathematical) way to determine the deadlock occurrence?
d. resource allocation graph
c. inversion graph
b. deadlock occurrence graph
a. starvation graph
287. To ensure that the hold and wait condition never occurs in the system, it must be ensured that
d. all the mentioned
c. a process can request resources only when it has none
b. each process must request and be allocated all its resources before it begins its execution
a. whenever a resource is requested by a process, it is not holding any other resources
288. If no cycle exists in the resource allocation graph
c. then the system will be in a safe state
b. then the system will not be in a safe state
a. all the mentioned
289. The memory allocation scheme subject to “internal” fragmentation is?
d. fixed partitioning
c. virtual memory segmentation
b. pure demand paging
a. segmentation
290. Thrashing _______ the CPU utilization
d. increases
c. none of the mentioned
b. decreases
a. keeps constant
291. The data structures available in the Banker’s algorithm are (выберите один или несколько ответов)
c. all of the mentioned
d. available
b. need
a. allocation
292. Each request requires that the system consider the _______ to decide whether the current request can be satisfied or must wait to avoid a future possible deadlock
d. future requests and releases of each process
c. resources currently available
b. processes that have previously been in the system
a. resources currently allocated to each process
293. What is the drawback of banker’s algorithm
d. the number of processes does not change as time progresses
c. in advance processes rarely know that how much resource they will need
b. resources are always available
294. For a deadlock to arise, which of the following conditions must hold simultaneously? (выберите один или несколько ответов)
d. hold and wait
c. all the mentioned
b. no preemption
a. mutual exclusion
295. Memory partitioning algorithm that uses binary tree as a data structure is called
d. Next-fit algorithm
c. Best-fit algorithm
b. First-fit algorithm
a. Buddy system
296. A mutex
d. is a hexademical value
c. must be accessed from only one process
b. can be accessed from multiple processes
a. cannot be accessed by processes
297. ________ replacement allows each process to only select from its own set of allocated frames
d. universal
c. global
b. public
a. local
298. LRU page - replacement algorithm associates with each page the ________
d. time it was brought into memory
c. the time of that page’s last use
b. all of the mentioned
a. page after and before it
299. Which of the following is true?
d. Overlays are used to increase the size of physical memory
c. Overlays are used to increase the logical address space
b. When overlays are used, the size of a process is not limited to the size of the physical memory
a. Overlays are used whenever the physical address space is smaller than the logical address space
300. The bounded buffer problem is also known as
d. Readers - Writers problem
c. Dining - Philosopher problem
b. Banker’s algorithm
a. Producer - Consumer problem
301. Semaphore operation semV() is alternative to
d. semaphore initialization
c. semaphore read
b. sem.signal()
a. sem.wait()