Question

18. You have a byte-addressable virtual memory system with a two-entry TLB, a 2-way set associative cache, and a page table for a process P. Assume cache blocks of 8 bytes and page size of 16 bytes. In the system below, main memory is divided into blocks, where each block is represented by a letter. Two blocks equal one frame. Given the system state as depicted above, answer the following questions: a) How many bits are in a virtual address for process P? Explain. b) How many bits are in a physical address? Explain. c) Show the address format for virtual address 180 (specify field name and size) that would be used by the system to translate to a physical address and then trans- late this virtual address into the corresponding physical address. (Hint: convert 18 to its binary equivalent and divide it into the appropriate fields.) Explain how these fields are used to translate to the corresponding physical address. d) Given virtual address 60 converts to physical address 54o. Show the format for a physical address (specify the field names and sizes) that is used to determine the cache location for this address. Explain how to use this format to deter- mine where physical address 54 would be located in cache. (Hint: Convert 54 to binary and divide it into the appropriate fields.) e Given virtual address 251o is located on virtual page 1, offset 9. Indicate exactly how this address would be translated to its corresponding physical address and how the data would be accessed. Include in your explanation how the TLB, the page table, cache, and memory are used. Page Frame TAG DATA TAG DATA Set 0 00 C 0I Set 1 A10 TLB D13 Frame Valid 10 L 11 M 12 N 13 O 14 P 15 A 6 Page Table Main Memory Virtual Memory for Process P

Answer 1

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