hpca/sample-final/samplefinal2/problem2

Problem 2. 15 Points – More caches

A processor has a 16-way set-associative, write-back, write-allocate, physically indexed,

4kB cache with 16-byte lines. Starting with an empty cache (all lines invalid), the

processor begins zeroing out the elements of an array that begins at physical address

0x40fbfca8 and is 0x4000 bytes long. Pages are 1MB in size. Each element of the array

is four bytes in size and the processor writes a zero into each element from first to last,

without accessing any other memory locations.

A) [3 points] By the time the zeroing-out is done, how many cache misses will have

occurred?

B) [4 points] Which set in the cache will be the first one to not have any non-valid

(empty) lines left? Answer: Set _______________.

C) [4 points] By the time the zeroing-out is done, how many write-backs will have

occurred?

D) [4 points] What is the tag of the last cache line to be written back to memory?