→ lovebluetea:因為1.1是memory access "per instrution"的次數 03/08 18:47
→ lovebluetea:要求的是cpi 若hit才算的話 會變成hit的MEM次數沒算 03/08 18:50
題目如下：
A computer system has L1 and L2 cache. The local hit rates for
L1 and L2 are 90% and 80%, respectively. The miss penalties are
10 and 50 cycles, respectively. Assuming a CPI of 1.2 without any
cache misses and an average of 1.1 memory accesses per instruction
(1)What is the average CPI after cache misses are factored in?
解答：
effective CPI=1.2+[(1-0.9)*0.8*10+(1-0.9)*(1-0.8)*(10+50)]*1.1
=3.4
想請問的是為什麼1.1是乘在那個地方？
我的想法是只要當L1和L2都miss，也就是必須要存取到記憶體時再
乘1.1就好，這樣的想法是錯在哪裡呢？
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