Effective time and hit ratios.

I am not able to now when do we have to add access time of cache to the main memory when a miss occurs, and when not to add in case of cache miss. Like,

EAT=  (h * tc) + (1-h)(tc+tm)   or

EAT=  (h * tc) + (1-h)(tm)

Parimal Andhalkar @parimal_andhalkar 16 Jan 2016 07:17 pm

first formula is for strict hierarchy 

2nd is for simultaneous access

you have to analyze it from question , which formula to be used.