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In computer science, a multilevel feedback queue is a scheduling algorithm. Solaris 2.6 Time-Sharing (TS) scheduler implements this algorithm.〔http://pages.cs.wisc.edu/~remzi/solaris-notes.pdf〕 The Mac OS X and Microsoft Windows schedulers can both be regarded as examples of the broader class of multilevel feedback queue schedulers.〔Operating Systems and Middleware: Supporting Controlled Interaction, Max Hailperin, 2007, p. 61〕 This scheduling algorithm is intended to meet the following design requirements for multimode systems: #Give preference to short jobs. #Give preference to I/O bound processes. #Separate processes into categories based on their need for the processor. The Multi-level Feedback Queue scheduler was first developed by Fernando J. Corbató et al. in 1962, and this work, along with other work on Multics, led the ACM to award Corbató the Turing Award. 〔(Scheduling: The Multi-Level Feedback Queue )〕 == Process Scheduling == Unlike multilevel queue scheduling algorithm where processes are permanently assigned to a queue, multilevel feedback queue scheduling allows a process to move between queues. This movement is facilitated by the characteristic of the CPU burst of the process. If a process uses too much CPU time, it will be moved to a lower-priority queue. This scheme leaves I/O-bound and interactive processes in the higher priority queues. In addition, a process that waits too long in a lower-priority queue may be moved to a higher priority queue. This form of aging also helps to prevent starvation of certain lower priority processes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Multilevel feedback queue」の詳細全文を読む スポンサード リンク
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