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10.(5%)In operating systems, the scheduler performs a rescheduling when current process requests an I/O, the time slice assigned to current process is exhausted, the current process yields, or higher-priority processes arrive. On every rescheduling, it will take time for the kernel to perform context switch. Is it possible for a round-robin scheduler with a 100-millisecond time slices to spend over half its time in the OS context switch code? Assume that it take the OS 1 millisecond to context switch the CPU. Please justify your answer and give an example. 這題看不懂,求強者幫忙解惑 Given a computer system with a 52-bit virtual address, 4 KB pages, and 4 bytes per page entry. Suppose that the maximum physical memory size is 512 GB, and the system is byte-addressable. Let paging be implemented for the system. What is the number of bits for physical addresses, and what is the maximum number of pages for a process? 52-bit virtual address → 252/4KB → 240 pages for a process. 想問答案b為什麼是這樣算~? 要求process占用的page個數 不是應該從phisical memory著手嗎? 謝謝 -- ┌這?─────────────────────────────┐ │ │ 一"一 \ / >\\\< ╯ ╰ ∩ ∩ ▁ ▁_< ㄧ ㄧ+ │ ε Δ ╰╯ 北七 亂喔 害羞 莎笅 爽啦 哭爸 XD 科科 └──────────────────────────────────────┘ -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 122.116.14.2 ※ 編輯: polomoss 來自: 122.116.14.2 (01/19 00:17)
honestonly:科科 01/19 00:28
zeowo:標題錯誤 01/19 19:35
imnewlegend:= = 01/20 04:08