[理工] 交大OS 幾題

看板Grad-ProbAsk作者Transfat (Transfat)時間7年前 (2017/01/09 22:25)推噓8(8推 0噓 18→)

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[104 交大OS] 12(d) Using on-line compaction can efficiently conquer the fragmentation prob lem of contiguous allocation. 有人可以解釋一下嗎？答案是false. 17(a) Trying to allow some instructions to take fewer cycles does not help, since the throughput is determined by the clock cycles; the number of pipeline stages per instruction affects latency, not throughput. 題目是在問下列敘述何者正確，答案給(a)正確，我觀念有點不太清楚，會影響throughput 的因素有哪些啊？且pipeline stages per instructoin,在single-cycle machine中不就是1嗎？他會影響latency ? [103交大OS] 3(b) The address space of a process can exceed the total size of installed RAM , system paging files, and swap partition. 這題題目說是True. 想問這邊的swap partition是指secondary store或是Disk的意思嗎？且我怎麼想也不覺得process可以用的address space可以超過這些記憶體的total size呀 7(a) The main reason why CPU's working frequency does not increases significantly these years is that CPU designers focus to push CPU architecture to multi-core voltage. 我..說不出這敘述哪裡怪怪的，知識不足QQ. 答案說這是false. 題組B (17)(18) http://imgur.com/a/RfXnY 這題可以解釋一下怎麼去評估maximum number of application 的使用量嗎？ [102交大OS] 16(e) The page fault of a running process has nothing to do with the program struture of the running process. 想問這邊的program structure 不是類似像資料結構或演算法等的code編排嗎？會發生 page fault是因為想要的東西不在memory裡面，跟我code scheduling有啥麼關係呢？（我在想還是是像loop unrolling那樣重複存取之類的？） ps: 102交大真是靠北難,真心酸 [101交大OS] 4(c) To reduce the overhead of page replacement, we can use a modify bit(or dirty bit) and select modified pages as victim pages. 這句話錯在..? 答案給false. 8. http://imgur.com/a/Y9bCy 想問什麼叫 log-structured file system? 還有為什麼要選(b) Disk reads不會比Disk write快嗎？知識不足QQ 14. http://imgur.com/a/qY0El 這題page size=4KB ---> offset=12, 所以VPN=16-12=4,我找virtual address的前面4個 bits(就是1,2,1,3,0,2,9,3,...)插入frames中去算，結果都是錯的，是我哪裡觀念搞錯了嗎？先這樣，謝謝你們 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 140.112.25.105 ※ 文章網址: https://www.ptt.cc/bbs/Grad-ProbAsk/M.1483971924.A.542.html

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