[理工] OS - E.A.T

看板Grad-ProbAsk作者JacobSyu (JacobSyu)時間9年前 (2015/01/20 21:22)推噓2(2推 0噓 15→)

留言17則, 3人參與討論串1/1

E.A.T存取時間,是否包含data block/frame(in memory)存取時間? Assume that the page to replaced is modified 70 percent of the time. What is the maximum acceptable page-fault rate for an effective access time of no more than 200 nanoseconds? Sol: (Note: 1 millisecond = 1,000,000 nanoseconds = 1e6 nanoseconds) EAT = (1-p)*(100) + (p)*(100 + (1-.7)*(8msec) + (.7)*(20msec)) = 100 - 100p + 100p + (2.4e6)*p + (14e6)*p = 100 + (16.4e6)*p 200 = 100 + (16.4e6)*p p = 100/16.4e6 (1-p)*100: 這100應該是指存取data block(frame)? -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 49.158.67.140 ※ 文章網址: https://www.ptt.cc/bbs/Grad-ProbAsk/M.1421760147.A.D51.html

→

JacobSyu

01/20 23:33, , 1^F

01/20 23:33, 1^F

→

wabesasa

01/21 17:43, , 2^F

01/21 17:43, 2^F

推

qoojordon

01/21 19:40, , 3^F

01/21 19:40, 3^F