PerformancePub Date : 1980-08-01DOI: 10.1145/1009375.806155
Raymond A. Marie
{"title":"Calculating equilibrium probabilities for λ(n)/Ck/1/N queues","authors":"Raymond A. Marie","doi":"10.1145/1009375.806155","DOIUrl":"https://doi.org/10.1145/1009375.806155","url":null,"abstract":"","PeriodicalId":32394,"journal":{"name":"Performance","volume":"265 1","pages":"117-125"},"PeriodicalIF":0.0,"publicationDate":"1980-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78861836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/1009375.806144
K. Chandy, C. H. Sauer
{"title":"Computational algorithms for product form queueing networks","authors":"K. Chandy, C. H. Sauer","doi":"10.1145/1009375.806144","DOIUrl":"https://doi.org/10.1145/1009375.806144","url":null,"abstract":"In the last two decades there has been special interest in queueing networks with a product form solution. These have been widely used as models of computer systems and communication networks. Two new computational algorithms for product form networks are presented. A comprehensive treatment of these algorithms and the two important existing algorithms, convolution and mean value analysis, is given.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75863361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806169
C. U. Smith, J. Browne
{"title":"Aspects of software design analysis: Concurrency and blocking","authors":"C. U. Smith, J. Browne","doi":"10.1145/800199.806169","DOIUrl":"https://doi.org/10.1145/800199.806169","url":null,"abstract":"This paper extends previous work on development of a methodology for the prediction of the performance of computer software systems from design level specifications and continuing through implementation. The effects of synchronized behavior, such as results from data reservation in multi-thread executions of data base systems, and competition for host system resources are incorporated. The previous methodology uses hierarchical graphs to represent the execution of software on some host computer system (or on some abstract machine). Performance metrics such as response time were obtained from analysis of these graphs assuming execution of a single copy on a dedicated host. This paper discusses the mapping of these execution graphs upon queueing network models of the host computing environment to yield performance metric estimates for more complex and realistic processing environments.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73849978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806155
Raymond A. Marie
{"title":"Calculating equilibrium probabilities for &lgr;(n)/Ck/1/N queues","authors":"Raymond A. Marie","doi":"10.1145/800199.806155","DOIUrl":"https://doi.org/10.1145/800199.806155","url":null,"abstract":"Equilibrium state distributions are determined for queues with load-dependent Poisson arrivals and service time distributions representable by Cox's generalized method of stages. The solution is obtained by identifying a birth-death process that has the same equilibrium state distribution as the original queue. Special cases of two-stage (C2) and Erlang-k (Ek) service processes permit particularly efficient algorithms for calculating the load - dependent service rates of the birth-death process corresponding to the original queue. Knowing the parameters of the birth-death process, the equilibrium state probabilities can be calculated straight-forwardly. This technique is particularly useful when subsystems are reduced to flow-equivalent servers representing the complementary network.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77769421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806173
K. Kim, Mahmoud Naghibzadeh
{"title":"Prevention of task overruns in real-time non-preemptive multiprogramming systems","authors":"K. Kim, Mahmoud Naghibzadeh","doi":"10.1145/800199.806173","DOIUrl":"https://doi.org/10.1145/800199.806173","url":null,"abstract":"Real-time multiprogramming systems, in which a hardware processor is dynamically assigned to run multiple software processes each designed to control an important device (user), are considered. Each software process executes a task in response to a service request repeatedly coming from the corresponding user. Each service task is associated with a strict deadline, and thus the design problem that we are concerned with is to ensure that the service tasks requested can always be executed within the associated deadlines, i.e., no task overrun occurs. This problem was studied by several investigators for the cases where preemptive scheduling strategies are used. In contrast, very few studies have been conducted for cases of non-preemptive scheduling. In this paper we show that a non-preemptive strategy, called relative urgency non-preemptive (RUNP) strategy, is optimal in the sense that if a system runs without a task overrun under any non-preemptive strategy, it will also run without a task overrun under the RUNP strategy. Then an efficient procedure used at the design time for detecting the possibility of a task overrun in a system using the RUNP strategy is presented. The procedure is useful in designing overrun-free real-time multiprogramming systems that yield high processor utilizations. Some special types of systems using the RUNP strategy for which even simpler detection procedures are available are also discussed.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"101 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77269790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806168
Y. T. Wang
{"title":"Analysis of an intrinsic overload control for a class of queueing systems","authors":"Y. T. Wang","doi":"10.1145/800199.806168","DOIUrl":"https://doi.org/10.1145/800199.806168","url":null,"abstract":"We consider a priority queueing system which consists of two queues sharing a processor and in which there is delayed feedback. Such a model arises from systems which employ a priority assignment scheme to achieve overload control. An analytic expression for the stationary probability of the queue lengths is derived. An algorithm is proposed to compute the queue lengths distribution. Some numerical results are illustrated.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77691469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806164
R. Bryant
{"title":"On homogeneity in M/G/1 queueing systems","authors":"R. Bryant","doi":"10.1145/800199.806164","DOIUrl":"https://doi.org/10.1145/800199.806164","url":null,"abstract":"Operational analysis replaces certain classical gueueing theory assumptions with the condition of “homogeneous service times.” In this paper, we show that the sample paths of an M/G/1 queueing system have this property with non-zero probability if and only if the service time distribution is exponential. We also consider the relationship of the operational performance measures S(n) and the mean service time. This relationship is shown to depend on the form of the service distribution. It follows that using operational analysis to predict the performance of an M/G/1 queueing system when the mean service time is changed will be most successful when the service time distribution is exponential. Simulation evidence is presented which supports this claim.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89584843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806156
R. Wagner, Kishor S. Trivedi
{"title":"Hardware configuration selection through discretizing a continuous variable solution","authors":"R. Wagner, Kishor S. Trivedi","doi":"10.1145/800199.806156","DOIUrl":"https://doi.org/10.1145/800199.806156","url":null,"abstract":"This paper extends a previous model for computer system configuration planning developed by the authors. The problem is to optimally select the CPU speed, the device capacities, and file assignments so as to maximize throughput subject to a fixed cost constraint. We advocate solving this essentially discrete problem in continuous variables followed by an appropriate discretization. The discretization error thus committed is analyzed in detail.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75552911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806153
A. Brandwajn
{"title":"Further results on equivalence and decomposition in queueing network models","authors":"A. Brandwajn","doi":"10.1145/800199.806153","DOIUrl":"https://doi.org/10.1145/800199.806153","url":null,"abstract":"This paper addresses three aspects related to the notion of exact equivalence in queueing models. In many cases the parameters of a system equivalent to a given model involve only a small subset of conditional probabilities of the state of the original model given the equivalent one. It is shown that meaningful bounds may be obtained for the conditional probabilities of interest with little computational effort. Such bounds are useful in assessing processing capacities as well as the accuracy of approximate solutions. As a second point it is shown that the notion of exact equivalence may be easily extended to networks with non-exponential servers. This is done for both the methods of supplementary variables and for the imbedded Markov chain technique. Qualitative analysis of approximation methods is also discussed. Finally, numerical methods based on the notion of exact equivalence, i.e. operating on conditional probabilities, are considered.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84082396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PerformancePub Date : 1980-05-28DOI: 10.1145/800199.806175
G. Fayolle, P. King, I. Mitrani
{"title":"The solution of certain two-dimensional markov models","authors":"G. Fayolle, P. King, I. Mitrani","doi":"10.1145/800199.806175","DOIUrl":"https://doi.org/10.1145/800199.806175","url":null,"abstract":"A class of two-dimensional Birth-and-Death processes, with applications in many modelling problems, is defined and analysed in the steady-state. These are processes whose instantaneous transition rates are state-dependent in a restricted way. Generating functions for the steady-state distribution are obtained by solving a functional equation in two variables. That solution method lends itself readily to numerical implementation. Some aspects of the numerical solution are discussed, using a particular model as an example.","PeriodicalId":32394,"journal":{"name":"Performance","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1980-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86540249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}