Re: [OS] CPU utilization消失
※ 引述《garnettooo (絕代風華賈奈特)》之銘言：
還想請問大家這題的解析，因為根據題目所提供的情況，
Consider the system running ten tasks and one CPU bound task.Assume that
the I/O bound tasks issue an I/O operation once for every millisecond of
CPU computing and that each I/O operation takes 10 millisecond to complete.
Also assume that the context switching overhead is 0.1 millisecond and
that all processes are long-running tasks. What is the CPU utilization for
RR scheduler when:
(1)time quantum=1 millisecond
(2)time quantum= 10 millisecond
可以了解CPU burst(T)=1, I/O=10,context switch=0.1
(1)第一題沒有問題，因為T=Q,所以CPU utilization=T/S+T=1/1+0.1=1/1.1
(2)第二題我就不太了解為何會有20,畢竟Q=10,Q>T,所以應該是T/S+T=1/1+0.1,
為何會是答案所給的20/21.1呢？
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想請問n大留言中的圖片
時間軸前10個單位是包含一次CPU burst跟一次的I/O operation嗎？
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