about cache memory

Question

For a system with two levels of cache, we define the following notation:
 Tc1 = first-level cache access time
 Tc2 = second-level cache access time
 Tm = memory access time
 H1 = first-level cache hit ratio
 H2 = (first+second) level cache hit ratio.
Provide an equation to calculate the average time of a read operation.

Answer 1

following normal hierarchy (means you can search at a time in more than one particular memory) first search in cache₁ memory then cache₂ memory after that main memory.

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following strict hierarchy (means you can search at a time in one particular memory) first search in cache₁ memory then cache₂ memory after that main memory.

Comments

Thank you very much for helping. But is there another formula where we ignore the miss ratio of cache

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no... there is no formula where we can ignore the miss ratio of cache. and see i updated my solution... small fault is there in my previous solution i corrected it now...

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You helped me a lot thank you

but could you explain the solution to me briefly because I am studying for the exam and would like to know how you concluded the solution.