A page-replacement algo. minimizes the number of page faults by distributing heavily used pages evenly over all of memory. It associates with each page frame a counter of the number of pages that are associated with that frame, and the initial value of the coounters is 0. Then, to replace a page, it searches for the page frame with the smallest counter. The counters are increased whenver a new page is associated with that frame; and are decreased whenever one of the pages associated with that frame is no longer required. a) How many page faults occur for the algo. for the following reference string, for four page frames? 1,2,3,4,5,3,4,1,6,7,8,7,8,9,7,8,9,5,4,5,4,2. 这题在说什麽啊? 不太懂意思?? 可以顺便解个我看吗? 解前几个大概告诉我做法就好了 谢谢!! b) what's the minimum number of page faults for an optimal page replacement strategy for the reference string in part (a) with four page frames? 这题是用最佳策略法吗? 我算出来11次 不知道跟大家算的一不一样耶?? --

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