Assume that we have a computer that uses virtual memory. It has a TLB$,$

a cache, and a page table. Furthermore, we can assume the following:

$$ A TLB hit requires $5$ ns

$$ A cache hit requires $12$ ns

$$ A memory reference requires $25$ ns

$$ A disk reference requires $200$ ms $($this includes updating the page table, cache,

and TLB$)$

$$ The TLB hit ratio is $90\%$

$$ The cache hit rate is $98\%$

$$ The page fault rate is $\mathrm{.}001\%$

$$ On a page fault, the page is fetched from disk, and access is restarted. In other

words, you must re$-$do the access after the disk block is retrieved $($see Slide $57$ in

Chapter $6).$

$$ All references are sequential $($no overlap, nothing done in parallel$)$

For each of the following, provide the total time taken for the access. Again, you may

want to use the logic of Slide $57$ as a guide.

a$.$ TLB hit, cache hit

b$.$ TLB miss, page table hit, cache hit

c$.$ TLB miss, page table hit, cache miss

d$.$ TLB miss, page table miss