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Question

IS THE ANSWER 1.794??

Comments

Either hit or miss ratio can't be greater than 1.

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oh yess,

then what is the correct answer??

i know answer given in solution is wrong!!

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see where am i wrong??

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@Shubhanshu

??

any idea??

am still confused!!not getting it

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is the hit ratio = 0.7983??

pls check @Shubhanshu

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@Gate Fever check this out:-

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you calculated miss ratio blockwise not element wise , why??

i also got same no. of misses,but element wise

first time total no. of misses will be 6, yes!

so i did it like this :-

on 42 elements there will be 6 misses; total misses =6/42

now when loop goes from 2nd iteration to 10th iteraion

in each iteration we have 2 misses on 34 elements

so total misses = 2/34

hence total miss rate = 6/42 + 2/34  =  0.20168

hence hit ratio =  1-0.20168 = 0.7983

whts incorrect in this????

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you calculated miss ratio blockwise not element wise , why??

Because transfer between Cache memory to/from Main Memory is blockwise, not wordwise. 

on 42 elements there will be 6 misses; total misses =6/42

Ok.

 now when loop goes from 2nd iteration to 10th iteraion

in each iteration we have 2 misses on 34 elements

so total misses = 2/34

from 2nd to 10th there are 9 iterations. And in each iteration, there are 2 misses and 2 hits. So total hit and miss will be $18$.

You have to take misses for all 9 iterations, not for the single iteration. thus getting $\frac{18}{42}$

So miss ratio will be $\frac{6}{18} + \frac{18}{42} = \frac{24}{42}$

And  hit ratio will be $\frac{18}{42}$

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 now when loop goes from 2nd iteration to 10th iteraion 

in each iteration we have 2 misses on 34 elements

 therefore (2*9)/(34*9) thats why 2/34

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What formula are using for Miss ratio calculation?

Btw standard formyal to calculate miss ratio is   =   $\frac{\text{no of misses}}{\text{Total no of memory references}}$

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i dont know where ia m going wrong!!

ill solve it with a fresh mind again & then will see!!

one more thing Shubhanshu, from where can i prepare questions for I/O INTERFACE like for DMA,POLLING etc,

pls tell me a good source