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Higher Study | Operating Systems | Virtual Memory

Which one of the following statements is false?
Determine the number of page faults when references to pages occur in the following order : 1, 2, 4, 5, 2, 1, 2, 4. Assume that the main memory can accommodate 3 pages and the main memory already has the pages 1 and 2, with page one having brought earlier than page 2. (LRU page replacement algorithm is used) 
Determine the number of page faults when references to pages occur is the order – 1, 2, 4, 5, 2, 1, 2, 4. Assume that the main memory can accommodate 3 pages and the main memory already has the pages 1 and 2, with page 1 having brought earlier than page 2. (assume LRU i.e. Least-Recently-Used algorithm is applied)
In which one of the following page replacement algorithms it is possible for the page fault rate to increase even when the number of allocated frames increases? 
Recall that Belady’s anomaly is that the page-fault rate may increase as the number of allocated frames increases. Now, consider the following statements: S1: Random page replacement algorithm (where a page chosen at random is replaced) Suffers from Belady’s anomaly S2: LRU page replacement algorithm suffers from Belady’s anomaly Which of the following is CORRECT?
Consider a fully-associative data cache with 32 blocks of 64 bytes each. The cache uses LRU (Least Recently Used) replacement. Consider the following C code to sum together all of the elements of a 64 by 64 two-dimensional array of 64-bit double-precision floating point numbers. double sum (double A [64] [64] ) { int i, j ; double sum = 0 ; for (i = 0 ; i < 64; i++) for (j = 0; j < 64; j++) sum += A [i] [j] ; return sum ; } Assume all blocks in the cache are initially invalid. How many cache misses will result from the code?
How many page faults will occur if FIFO Page replacement algorithm is used for the following reference string with three-page frames? 7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1, 7, 0, 1
How many page faults will occur if Optimal Page replacement algorithm is used for the following reference string with three page frames? 7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1, 7, 0, 1
A system uses FIFO policy for page replacement. It has 4 page frames with no pages loaded to begin with. The system first accesses 100 distinct pages in some order and then accesses the same 100 pages but now in the reverse order. How many page faults will occur?
A computer has sixteen pages of virtual address space but the size of main memory is only four frames. Initially the memory is empty. A program references the virtual pages in the order of 0, 2, 4, 5, 2, 4, 3, 11, 2, 10. How many page faults occur if LRU page replacement algorithm is used?
How many page faults occur in LRU page replacement algorithm for the given reference string, with four-page frames 7, 0, 1, 2, 0, 3, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1
How many page faults occur in a system with LRU page replacement policy having 3 (initially empty) page frames for the following string of page reference - 5, 1, 2, 3, 4, 3, 2, 3, 1, 2, 4, 3?
Given reference to the following pages by a program 0, 9, 0, 1, 8, 1, 8, 7, 8, 7, 1, 2, 8, 2, 7, 8, 2, 3, 8, 3 How many page faults will occur if the program has three page frames available to it and uses an optimal replacement?
A system uses FIFO policy for page replacement. It has 4 page frames with no pages loaded to begin with. The system first accesses 50 distinct pages in some order and then accesses the same 50 pages in reverse order. How many page faults will occur?
Consider a main memory with 3 page frames in the following sequence of page reference 3, 4, 2, 3, 9, 1, 6, 3, 4, 9. What is the number of page fault using FIFO page replacement algorithm?
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