# Operating System

QUESTION 1 [21 Marks] A paging system with an X-bytes of logical memory with some portions of logical addresses (decimal) with its contents as shown in Table 1 need to be mapped to an Y-bytes of physical memory based on the complete 22 entries for a page table shown in Table 2. Assume that each entry size is 22-bytes and the physical memory size is 26 frames. Answer the following questions. Table 1 Table 2 Logical Address 0 Content B Page # 0 Frame # 10 8 1 2 3 4 1 2 3 5 13 A D 5 G 6 K 7 8 19 20 F (a) Calculate the page size of the logical memory in bytes? [2] (b) Calculate the size of X and Y. Show your working. [4] (c) Calculate the number of bit that will be used for the page number in logical memory address and frame number in physical memory address? [4] (d) What will be the contents of frame 5? Justify your answer. [3] (e) Given the page number and the offset as 1:10 for logical address, calculate the physical address. [4] (1) Calculate the logical address (decimal) given a physical address as 100101102. Show your working. [4]