Gate Applied course Test series

Question

What is answer for this question and also please explain the approach

Answer 1

Actually all the options are wrong!!

200=p(100)+(1-p)(600)

where p is TLB hit rate

on solving the above equation

200=100p+600-600p

200=600-500p

500p=400

so p=4/5

And hence, p=0.8.

The other information(page size, 32 virtual pages) given is just to confuse you!!

 

Comments

You have written the wrong formula mate. No sense in going with only TLB lookup time without going for Main memory access time.

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there is nothing wrong. If you read the question carefully it is asking about the time required to translate the logical address. It is not asking about the total time required to translate the logical address and fetch it’s corresponding instruction. 

So the translation can be found either in the TLB if it’s page hit, and if its page miss then we need to find the translation in page table residing in MM.

 

Answer 2

i am getting 0.7 is it right?

Comments

can you please explain your approach?

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200 =   hit  * (100+32)   +  (1-hit) (100+32+500)

hit=0.7

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@jugnu1337 why have you added 32?