cache

Question

I read in cache           Effective time = hit ratio * cache access time + miss ratio*memory access time

why not in miss penalty the additional searching in cache considered i.e. Penalty = memory access time + cache access time as unnecessary we need to search cache right?

Comments

accessing cache and searching cache are two different things...

cache searching time is almost negligible in every case, in case of cache hit also, the cache searching time is not taken in account since it is very less, only cache access time is needed..

and the formula given above is for parallel access, for hierarchical access what you have said is correct..

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and sir little more doubt how to know which of the access is used parallel or hierarchical
IS Parallel default or access will be specified in the Question

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generally specified in qsn...and i am not sir :)