Queueing Models for File Memory Operation

A model for the auxiliary memory function of a segmented, multiprocessor, time-shared computer system is set up. A drum system in particular is discussed, although no loss of generality is implied by limiting the discussion to drums. Particular attention is given to the queue of requests waiting f...

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Main Author: Denning, Peter James
Other Authors: Dennis, Jack B.
Published: 2023
Online Access:https://hdl.handle.net/1721.1/149343
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author Denning, Peter James
author2 Dennis, Jack B.
author_facet Dennis, Jack B.
Denning, Peter James
author_sort Denning, Peter James
collection MIT
description A model for the auxiliary memory function of a segmented, multiprocessor, time-shared computer system is set up. A drum system in particular is discussed, although no loss of generality is implied by limiting the discussion to drums. Particular attention is given to the queue of requests waiting for drum use. It is shown that a shortest access time first queue discipline is the most efficient, with the access time being defined as the time required for the drum to be positioned, and is measured from the finish of service of the last request to the beginning of the data transfer for the present request. A detailed study of the shortest access time queue is made, giving the minimum access time probability distribution, equations for the number in the queue, and equations for the wait in the queue. Simulations were used to verify these equations; the results are discussed. Finally, a general Markov Model for Queues is discussed in an Appendix.
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spelling mit-1721.1/1493432023-03-30T04:04:47Z Queueing Models for File Memory Operation Denning, Peter James Dennis, Jack B. A model for the auxiliary memory function of a segmented, multiprocessor, time-shared computer system is set up. A drum system in particular is discussed, although no loss of generality is implied by limiting the discussion to drums. Particular attention is given to the queue of requests waiting for drum use. It is shown that a shortest access time first queue discipline is the most efficient, with the access time being defined as the time required for the drum to be positioned, and is measured from the finish of service of the last request to the beginning of the data transfer for the present request. A detailed study of the shortest access time queue is made, giving the minimum access time probability distribution, equations for the number in the queue, and equations for the wait in the queue. Simulations were used to verify these equations; the results are discussed. Finally, a general Markov Model for Queues is discussed in an Appendix. 2023-03-29T14:51:37Z 2023-03-29T14:51:37Z 1965-10 https://hdl.handle.net/1721.1/149343 14193236 MIT-LCS-TR-021 MAC-TR-021 application/pdf
spellingShingle Denning, Peter James
Queueing Models for File Memory Operation
title Queueing Models for File Memory Operation
title_full Queueing Models for File Memory Operation
title_fullStr Queueing Models for File Memory Operation
title_full_unstemmed Queueing Models for File Memory Operation
title_short Queueing Models for File Memory Operation
title_sort queueing models for file memory operation
url https://hdl.handle.net/1721.1/149343
work_keys_str_mv AT denningpeterjames queueingmodelsforfilememoryoperation