→ f1256421: 因為是用word為單位 01/18 13:25
→ a37805: word address喔 看清楚 01/19 00:13
題目如下
Cache1:direct-mapped with one word block
Cache2:direct-mapped with four word block
Cache3:two-way set associated with two block and use LRU
assuming that each cache has a total data size of 16 32-bit words and
all of them are initially empty. 20 bit word address used.
a.以上三個cache的TAG大小
張凡答案給
cache 1: 16 bits (20-4 = 16)
為什麼不用考慮 Byte Offset?
我的算法是 因為Direct mapped 所以 在cache1的情況下 有 16個block
每個block 有4 byte 所以 offset = 2 bit (Word Offset =0 , Byte Offset=2)
又因為cache只有16 block 且是Direct Mapped方法 所以index = 4 bit
所以 Tag = 20 - 4 - 2 = 14 bits
我和朋友 都卡在這 是題目看錯？
請大神ＣＡＲＲＹ
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