CS220 - 04.ppt
Transcript of CS220 - 04.ppt
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- 2n K , M=2n/K. C (C
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, , 64kB, 4B. 16k=214 4B.
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16MB 24- (224=16).
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i = j mod m i j m
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. . w .
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s 2s . s s-r ( ) r . m=2r .
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= (s+w) . = 2s+w. = = 2w. = 2s+w/ 2w= 2s. = m = 2r . = (s-r) .
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. 00, 01, ..., FF.
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= (s+w) . = 2s+w. = = 2w. = 2s+w/ 2w= 2s. = . = s .
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v k :m = vki = j mod v i j m
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k- - . Bj i.
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: , . d v=2d . s 2s .
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. 9. k- - .
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= (s+w) . = 2s+w. = = 2w. = 2s+w/ 2w= 2s. = k = v=2d = kv=k2d. = (s-d) .
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:LRU (Least Recently Used).FIFO (First In First Out)LFU (Least Frequently Used)
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.Write through: .Write back: .
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., / !
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: . , . , . / 8-32 HPC 64-128.
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on-chip . off-chip . : L1 (on-chip) i L2 (off-chip).
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on-chip , . : . .
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, , (Pentium PowerPC). / .