Re: [理工] [計組]-東華93-資工

[cakeboy ()]

※ 引述《starbury8 (馬不理不思議)》之銘言：
: Assume that we have an array of four disks.
: Eacg disk has 16 sectors per track, each track holds 1KB of data,
: and the revolves at 3750 RPM.
: Assume that the seek time is 6ms,
: the delay of the disk controller is 1ms per transaction.
: Assume that the requests are random reads of
: 4KB of data from sequential sectors.
: Please calculate the performance in KB per second for this system.
: 請問這題的transfer time怎麼看??

磁碟轉一圈可以讀一個cylinder

一個cylinder=track*sector*1kB

所以transfer rate=62.5*16*1kb=1000kB/sec

應該是這樣

trans time 4kb/1000kb/sec=4ms
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◆ From: 61.231.176.236
※ 編輯: cakeboy         來自: 61.231.176.236       (10/07 22:44)
※ 編輯: cakeboy         來自: 61.231.176.236       (10/07 22:45)
推 starbury8:請問式子裡的track是指??
→ starbury8:另外cylinder的話 為什麼不用*4個硬碟呢? 謝謝!!
推 hunter0904:你可能要去找DISK的介紹= =track是磁軌一圈一圈的
→ cakeboy:track就是從圓心到最外圍一圈一圈的,硬碟是分開的
推 starbury8:我知道track是什麼啦XD 是問說那個變數"track"要帶多少