Showing papers on "Fair-share scheduling published in 1980"
434 citations
TL;DR: New heuristic scheduling rules are determined which give high performance for flow-shop scheduling where there is (i) no job-passing and (ii) noJob-waiting.
Abstract: Existing methods are reviewed and new heuristics examined and developed for the flow-shop scheduling problem. Comparative tests are carried out using simulation methods on different sizes of problem and with different variability of processing time data. New heuristic scheduling rules are determined which give high performance for flow-shop scheduling where there is (i) no job-passing and (ii) no job-waiting.
189 citations
TL;DR: A scheduling algorithm for a set of tasks that guarantees the time within which a task, once started, will complete is described.
Abstract: This paper describes a scheduling algorithm for a set of tasks that guarantees the time within which a task, once started, will complete. A task is started upon receipt of an external signal or the completion of other tasks. Each task has a rxed set of requirements in processor time, resources, and device operations needed for completion of its various segments. A worst case analysis of task performance is carried out. An algorithm is developed for determining the response times that can be guaranteed for a set of tasks. Operating system overhead is also accounted for.
162 citations
TL;DR: This article discusses several candidate techniques for schedule determination, and these are evaluated in a specific radar scheduling application.
Abstract: Consider a set of task pairs coupled in time: a first (initial) and second (completion) tasks of known durations with a specified time between them. If the operator or machine performing these tasks is able to process only one at a time, scheduling is necessary to insure that no overlap occurs. This problem has a particular application to production scheduling, transportation, and radar operations (send-receive pulses are ideal examples of time-linked tasks requiring scheduling). This article discusses several candidate techniques for schedule determination, and these are evaluated in a specific radar scheduling application.
69 citations
TL;DR: In this paper, the authors present a model for airline flight schedules that takes into account the complex interaction between the passenger and aircraft routing components, and the solution time is kept low by the use of powerful mathematical programming techniques.
Abstract: The model described determines airline flight schedules which will maximise company profits and passenger satisfaction. The approach represents a significant improvement in analytical methods for fleet planning and scheduling which take into account the complex interaction between the passenger and aircraft routing components. In spite of the high level of detail in the description of these components, the solution time is kept low by the use of powerful mathematical programming techniques. Moreover, the model can easily be adapted to deal with several different formulations.
52 citations
TL;DR: An algorithm to preemptively schedule n tasks on m uniform processors that schedules all tasks to complete by their due times whenever possible and generates O(mn) preemptions in the worst case.
Abstract: An algori thm to preemptively schedule n tasks on m uniform processors is presented. It is assumed that each task is available at t ime 0. Associated with each task is a due time by which it is to be completed. The algorithm schedules all tasks to complete by their due times whenever possible. The asymptotic time complexity of the algorithm is O(n log n + ran). It generates O(mn) preemptions in the worst case. An example of n tasks requiring O(mn) preemptions is also presented. The algorithm can also be used when all tasks have the same due times but different release times.
51 citations
TL;DR: A deterministic approach to the preemptive scheduling of independent tasks, which takes into account primary memory allocation in multiprocessor systems with virtual memory and a common primary memory is proposed.
Abstract: This paper proposes a deterministic approach to the preemptive scheduling of independent tasks, which takes into account primary memory allocation in multiprocessor systems with virtual memory and a common primary memory. Each central processing unit (CPU) is assumed to have dedicated paging devices and thus paging- device competition does not exist in the system. The system workload is based on an analytic approximation to the lifetime curve of a task. Exact and approximate algorithms are presented which minimize or tend to minimize the length of schedules on an arbitrary number of identical processors. In the general case, the exact algorithm is based on nonlinear programming; however, the approximate algorithm requires the solution of several nonlinear equations with one unknown. For certain cases, analytical results have also been obtained.
42 citations
36 citations
01 Feb 1980
TL;DR: For solving greater problems some modifications are discussed at the end of the paper, which are essentially based on the notion of “heuristic efficiency”.
Abstract: A mixed integer multiple criteria model is formulated for scheduling problems. Its solution is obtained by an interactive method based on the Tchebycheff-approximation. For solving greater problems some modifications are discussed at the end of the paper, which are essentially based on the notion of “heuristic efficiency”.
30 citations
TL;DR: In this article, a large petrochemical plant is modeled as a job shop where the orders are of two types, emergency and non-emergency, and the emergency orders can be delayed until later.
Abstract: A maintenance planning and scheduling system often resembles that of a ‘job shop’ that is, the orders are one of a kind, and is characterized by having to schedule N orders through M or less tasks. The orders are of two types, e.g., (a) emergency—have to be done now, and (b ) non-emergency—can be delayed until later. In this type of ‘job shop’ the schedule becomes immediately out of date as soon as an emergency order is received. Consequently non-emergency orders are continually moved back in the schedule and forecasted completion dates are not met. Further if the orders entering the system exceed the normal available capacity, the backlog will continue to increase causing more disruption of schedules. The research, which is based on a large petrochemical plant, will deal with the above problems by (a) applying dynamic decision rules for day-to-day scheduling to ensure completion dates are met, (b) a method for controlling backlog, and (c) forecasting future load, and completion dates for orders. The resu...
20 citations
TL;DR: The preemptive scheduling of a partially ordered set of tasks is studied, and a class of scheduling heuristics is introduced that indicate that there are schedules which may be as bad as $\sqrt{m-1}$ times worse than optimal even for machines with one fast processor.
Abstract: The preemptive scheduling of a partially ordered set of tasks is studied. A class of scheduling heuristics is introduced, and the performance of schedules in this class is analyzed with respect to the least finishing time optimality criterion. If there are m processors, then the finishing time of any schedule in the class is at most $\sqrt{m} + 1/2$ times worse than optimal, independent of the speeds of the processors. Examples are given which indicate that there are schedules which may be as bad as $\sqrt{m-1}$ times worse than optimal even for machines with one fast processor.
13 Oct 1980
TL;DR: An algorithm with running time O(n310g n) which schedules all the jobs while minimizing the maximum job completion time is described.
Abstract: The problem we discuss is that of scheduling n unit-time jobs, with release times and deadlines which are arbitrary real numbers, on m identical parallel machines. A polynomial time algorithm with time complexity O(n210g n) was first obtained. for the single machine case by Simons [5]. An alternative algorithm with the same time complexity was subsequently obtained by Carlier [1]. Most recently, an algorithm with time complexity O(n log n) has been presented in a paper by Garey, Johnson, Simons, and Tarjan [3]. In the multi-machine case the best previously known result was produced by Carlier, whose algorithm runs in time O(nm+ 210g n) [1]. However, the question of whether an algorithm exists which solves the problem in time which is polynomial in both m and n remained unanswered and was presented as an open problem in a paper by Garey, Johnson, Simons, and Tarjan [3]. We describe below an algorithm with running time O(n310g n) which schedules all the jobs while minimizing the maximum job completion time.
TL;DR: In this article, it was shown that a problem which arose in the scheduling of two simultaneous competitions between a number of golf clubs may be reduced to that of 4-coloring the edges of a certain bipartite graph which has 4 edges meeting at each vertex.
Abstract: Abstract It is shown that a problem which arose in the scheduling of two simultaneous competitions between a number of golf clubs may be reduced to that of 4- colouring the edges of a certain bipartite graph which has 4 edges meeting at each vertex. This colouring problem is solved by an analysis in terms of directed cycles, which is simple to carry through in a practical case and is easily extended to the problem with 4 replaced by 2m. The more general colouring problem with 4 replaced by any positive integer is solved by relating it to the marriage problem enunciated by Philip Hall and to the latin multiplication technique of Kaufmann but, in practical applications, this approach involves severe computational difficulties.
TL;DR: A variety of modifications to this basic theme of scheduling tasks on a system consisting of two parallel processors in order that makespan be minimized are treated, including the cases of identical, proportional, and unrelated processors.
Abstract: This paper is concerned with the problem of scheduling tasks on a system consisting of two parallel processors in order that makespan be minimized. In particular, we treat a variety of modifications to this basic theme, including the cases of identical, proportional, and unrelated processors. In addition, a heuristic scheme is suggested when precedence constraints exist where such constraints may be assignment dependent. Substantial computational experience is reported in all cases where it would appear that relatively large problems can be handled routinely.
TL;DR: In this paper, a new method for solving perturbation problems in the course of production scheduling of cutting operations in the field of machine tool manufacture is presented, which can adapt machining times to actual production situations and therefore meet due dates without a need for overtime operation.
TL;DR: It has been found that a suitable selection of a state vector reduces greatly the dimensionality of the problem and an algorithm to solve the scheduling problem by using the concept of state vectors of dynamic programming is described.
Abstract: The single facility multiple products scheduling problem is formulated into a multiperiod mathematical programming model with zero-one variables. An algorithm to solve the scheduling problem by using the concept of state vectors of dynamic programming is described. An example of application of the model and the algorithm is also presented. It has been found that a suitable selection of a state vector reduces greatly the dimensionality of the problem
TL;DR: This paper develops both a probabilistic and a simulation model for evaluating the validity of a simple and apparently appealing heuristics approach to dealing with tapes and removable disks with high set-up time.
TL;DR: In this paper, an approach to the optimization of heuristic scheduling in batch and jobbing manufacture is described based upon the use of a composite weighted priority index to resolve conflicts between operations in order to meet a predefined management objective function.
Abstract: This paper describes an approach to the optimization of heuristic scheduling in batch and jobbing manufacture. The approach is based upon the use of a composite weighted priority index to resolve conflicts between operations in order to meet a predefined management objective function. The effects of combined despatching parameters in the priority index are investigated and examples are given of the resulting response surfaces. Using the techniques of harmonic analysis a model of the underlying surface trend is identified and used to predict the location of optimal schedules. Typical experimental results are presented which suggest that the proposed method compares favourably with traditional scheduling techniques.
Dissertation•
01 May 1980
TL;DR: This work presents an alternative model of task systems with resources in which the resources are discrete, that is, there are a specific number of indivisible units of each resource and a task may require only integral numbers of those units.
Abstract: Minimum execution time scheduling of task systems with resources has been the subject of several papers over the past few years. The model used for much of this work assumes that the resources associated with computer systems - readers, printers, disk drives - are not "continuous" resources. We present an alternative model of task systems with resources in which the resources are discrete. That is, there are a specific number of indivisible units of each resource and a task may require only integral numbers of those units. Several results involving the worst case performance of list scheduling and critical path scheduling with respect to this model are given. A new result on critical path scheduling of task systems with continuous resources is also given. Finally, a comparison will be made between corresponding bounds for the continuous and discrete models.
01 Jan 1980
TL;DR: A simulation approach to the comparative analysis of different job scheduling methods with regard to CPU efficiency, the job throughput, and the job waiting time is presented.
TL;DR: In this paper, a case history is presented from a 7,000 employee automotive transmission plant, which concerns a large transfer line department which could be viewed as a single machine production system with sequence-dependent setups.
Abstract: A case history is presented from a 7,000 employee automotive transmission plant. It concerns a large transfer line department which could be viewed as a single machine production system with sequence-dependent setups. The objective is to identify those elements that are necessary for success in implementing on-line systems with operating personnel in a production environment. This case is the first of a two-part series; Part II will detail a successful implementation.
28 Apr 1980
TL;DR: An upper bound for the worst case performance of critical path scheduling is given and it is shown that this is the best possible (asymptotic) upper bound.
Abstract: Minimum execution time scheduling of unit execution time (UET) task systems with resources has been the subject of several papers over the past few years. Because such scheduling problems are, in general, NP-hard, a variety of heuristic methods for producing schedules have been studied, among them, critical path scheduling. The strongest results to date have been for systems where there is no processor constraint. These results may be utilized for systems with a processor constraint by treating the processors as an additional resource. Unfortunately, in those cases where the number of processors is close to the number of resources, this results in an upper bound which is somewhat misleading. In this paper we investigate the performance of critical path scheduling for UET task systems with resources and a fixed number of processors. An upper bound for the worst case performance of critical path scheduling is given. This bound depends both on the number of processors and on the number of different resources. Moreover, we show that this is the best possible (asymptotic) upper bound.
TL;DR: This paper examines some problem of optimization of query processing in distributed data base systems and uses the notion of ‘process’ in the meaning of a quantity of work corresponding to the execution of either a subquery or relational operation.
01 Oct 1980
TL;DR: Analysis of analytically solvable queueing models of multiprogramming with different jobs and various scheduling disciplines shows that the analysis of these models supports the optimality of the already proposed CPU scheduling discipline which assigns higher processing priority to a more I/O bound job.
Abstract: Several analytically solvable queueing models of multiprogramming with different jobs and various scheduling disciplines are investigated. It is shown that the analysis of these models supports the optimality of the already proposed CPU scheduling discipline which assigns higher processing priority to a more I/O bound job. Furthermore, the effects of some endogenous scheduling disciplines such as preemptive-resume last-come-first-served are compared with that of this discipline using some queueing models.