※ 引述《christianSK (AG)》之銘言：
: 我想問兩個問題
: 98 中山資工 (題組中的一個小題)
: (c)
: Cache C1 is direct-mapped with 16 one-word blocks. Cache C2 is a direct-mapped
: with 4 foru-word blocks. Assume that the miss penalty for C1 is 4 memory bus
: clock cycles and the miss penalty for C2 is 7 memory bus clock cycles.
: Assuming that the caches are initially empty, find an address list for which
: C2 has a lower miss rate but spends more memory bus clock cycles on cache miss
: than C1. What are the corresponding miss rates for C1 and C2 in this reference
: string ?
: 好像跟a,b沒有關係 所以我就沒po了, 誤解的話麻煩告訴我一下 :)
: 不太懂題目的意思 希望有人可以教教我
它是說舉例找出c2有較小的miss rate但cycle會花的比c1多，要找出這個string
也就是~
c1的 ?miss rate x 4 miss penalty 會小於 c2的 ?miss rate x 7miss penalty
試一下，就取最小數 3x4 < 2x7也就是c1要找miss rate=3 c2要求miss rate=2
答案就是0x00000000,0x00000020,0x00000021分別帶入c1及c2就是分別所設的
miss rate...
不知道這樣看得懂嗎？....不好意思，趕時間！
: 96 交大電子
: Virtual memory
: (d) What are the benefits if a larger page size is chosen?(List at least 3.)
: What is the drawback?
: Ans:
: benefits: (1) more efficient to amortize the high access time
: (2) more spatial and temporal localities
: (3) smaller page table size
: drawbacks: (1) more internal fragmentation
: (2) higher miss penalty
: 對benefits中的(1) 不太能夠理解
: 是指說因為page size大一次傳進來比較多的資料, 這樣可以傳比較少次的意思嗎?
: 謝謝大家~
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