[理工] [計組]-cache

看板Grad-ProbAsk作者 (123)時間14年前 (2010/02/15 15:10), 編輯推噓1(1推 0噓 10→)
留言11則, 4人參與, 最新討論串2/2 (看更多)
大同資工97計組 A computer system has L1 and L2 caches. The local hit rates of L1 and L2 are 95% and 80%,respectively. The miss penalties are 8 and 60 cycles. Assuming a CPI of 1.2 without any cache miss and average of1.1 memory access per instruction, what is the effect CPI after cache missses are factored in ? 我列的式子 CPI= 0.95*1.2+0.05*0.8(1.2+8)+0.05*0.2(1.2+8+60) 題目給的1.1我不知到要怎麼用上= =? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 122.124.200.154
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02/15 15:21, , 1F
我列的是:1.2+1.1(0.05*8+0.05*0.2*60)
02/15 15:21, 1F
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02/15 15:24, , 2F
我不喜歡用課本那種列式，我覺得好難懂喔
02/15 15:24, 2F
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02/15 15:27, , 3F
如果用我這方法列1.1要怎麼用上？
02/15 15:27, 3F
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02/15 16:16, , 4F
你的式子就好整個加1.1 ，或者是每項都加1.1也一樣
02/15 16:16, 4F
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02/15 16:17, , 5F
另外我怎麼覺得一樓的式子怪怪的
02/15 16:17, 5F
推
02/15 16:19, , 6F
列的跟一樓一樣~
02/15 16:19, 6F
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02/15 16:21, , 7F
阿..我看懂了XD..一樓沒錯..原來是一個指令1.1memory
02/15 16:21, 7F
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02/15 16:26, , 8F
問一下1.1不用乘1.2嗎？
02/15 16:26, 8F
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02/15 16:33, , 9F
噗..我知道為什麼了XD
02/15 16:33, 9F
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02/15 16:33, , 10F
0.95*1.2+0.05*0.8(1.2+8*1.1)+0.05*0.2(1.2+(8+60)*1.1)
02/15 16:33, 10F
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02/15 16:33, , 11F
原po可以這樣列
02/15 16:33, 11F
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