Showing papers on "Server published in 1975"
TL;DR: An approximate procedure for computing selected performance characteristics of an urban emergency service system based on a recently developed hypercube queuing model that allows computation of several point-specific as well as area-specific performance measures.
Abstract: This paper presents an approximate procedure for computing selected performance characteristics of an urban emergency service system. Based on a recently developed hypercube queuing model, the procedure requires for N servers solution of only N simultaneous equations, rather than 2N as in the exact model. The procedure relies on the theory of M/M/N queues in which servers are selected randomly and without replacement until the first available free server is found. The underlying model is intended for analyzing problems of vehicle location and response district design in urban emergency services, includes interdistrict as well as intradistrict responses, and allows computation of several point-specific as well as area-specific performance measures.
361 citations
Dissertation•
01 Jan 1975
TL;DR: This paper presents a meta-modelling system that automates the very labor-intensive and therefore time-heavy and therefore expensive and expensive process of computer programming called “hacking”.
Abstract: Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.
56 citations
TL;DR: It is shown that an optimal policy may call for turning one or more servers off even when there are customers for him to serve, in an average cost, infinite horizon M/M/c problem.
Abstract: The form of optimal policy is investigated in an average cost, infinite horizon M/M/c problem where the number of servers working can be adjusted at arrival or service completion epochs. The costs considered are linear holding costs, linear servers' wages and set-up (shut-down) charges per server turned on (off). We show that an optimal policy may call for turning one or more servers off even when there are customers for him to serve.
18 citations
IBM1
TL;DR: This paper investigates the stationary behavior of a single server queuew ith different classes of jobs by finding the relationship between the timeAverage probability distribution and the departure average probability distribution.
Abstract: A computer system can usually be interpreted as a closed network with two different types of servers. It is then possible to convert the network into a single server system with state-dependent arrivals. This paper investigates the stationary behavior of a single server queuew ith different classes of jobs. It is assumed that the input process has state-dependent exponential inter-arrival times and preemptions at the server are not allowed. The exact solution is obtained by finding the relationship between the time average probability distribution and the departure average probability distribution. The latter can be derived based upon an imbedded Markov Chain.
9 citations
01 Jan 1975
TL;DR: In this article, the authors developed analytic techniques for achieving macro-level configurational optimization of computer systems, where the computer is viewed as a network of queues with the processors, main memory, auxiliary memory and the transfer channels being the servers.
Abstract: This paper develops analytic techniques for achieving macro-level configurational optimization of computer systems. The computer is viewed as a network of queues with the processors, main memory, auxiliary memory and the transfer channels being the servers. The objective function to be minimized is the total system cost divided by the probability of the CPU busy time for a given user benchmark. A queueing model is developed which evaluates this probability. The scope of optimization includes the determination of the parameters related to component selection and the determination of management oriented variables like degree of multiprogramming, main memory space allotted to each program. The optimization algorithm is a modified 'Direct Search Method'.
9 citations
TL;DR: The computer simulation model developed by the ABACUS research team in the Department of Architecture and Building Science at the University of Strathclyde is intended as an appraisal tool in the designing of airport terminal buildings such that the efficiency of alternative design solutions can be readily compared.
Abstract: The computer simulation model was developed by the ABACUS research team in the Department of Architecture and Building Science at the University of Strathclyde, Glasgow. The model is intended as an appraisal tool in the designing of airport terminal buildings such that the efficiency of alternative design solutions can be readily compared. This is essentially a ‘queueing model’ in which all possible activities in the terminal building are represented as a network of activity nodes , each of which is a potential queue situation where QUE size is determined by the exogenous variables ‘number of servers’ and ‘service time’. The simulation is time-based and monitors the variation in queue sizes over the time period being simulated for a given throughput of passengers, visitors, greeters etc. The model is deterministic and does not consider the effect of stochastic variations in service time. It is argued that such variations have little effect on systems as large and complex as airport terminals, however the same research team is investigating the inclusion of such techniques in the model.
5 citations
01 Feb 1975
TL;DR: An earlier poll of Telnet server implementation status revealed no change in the status of the Telnet client or server as well as no changes in the server itself.
Abstract: An earlier poll of Telnet server implementation status. Updates RFCs
701, 702 and 669; see also RFC 703.
4 citations
TL;DR: A multiserver queue with heterogeneous servers in which arriving customers are assigned to servers according to an autonomous Markov chain under conditions ensuring stability, stationary distributions are computed for the waiting times and the system response times of successive customers.
Abstract: This paper considers a multiserver queue with heterogeneous servers in which arriving customers are assigned to servers according to an autonomous Markov chain. Under conditions ensuring stability, stationary distributions are computed for the waiting times and the system response times of successive customers. Limits are also obtained for the expected system workload and the expected number of customers in the system.
2 citations
TL;DR: This work studies the queuing behavior of the sequential server systems with Poisson arrivals, general service time distributions, and several service disciplines, including bulk arrivals, message priorities, and the input and output queues.
Abstract: A queuing model with two sequential servers is developed to analyze performance in computer and communication systems. In one case the CPU is the first server and the terminal and its associated communications equipment are the second server. In a second case the CPU and the channel are the first server and the auxiliary storage device is the second server. We study the queuing behavior of the sequential server systems with Poisson arrivals, general service time distributions, and several service disciplines, including bulk arrivals, message priorities, and the input and output queues. The stationary distributions of the queue lengths and waiting times are determined by using an imbedded Markov chain analysis. Several examples are given to illustrate the applications of these models to practical problems.
2 citations
TL;DR: In this paper, the conditions under which this assumption is exact were investigated and the conditions for the existence of queues in a queue-based service system with queuing were investigated, assuming it to be reversible.
Abstract: A type of service system of particular interest in teletraffic theory has the property that calls (customers) originating from different sources have access to different subsets of a single group of devices (servers). One may or may not allow the formation of queues. Thierer [11], [12] has studied such a system with queues assuming it to be reversible. We investigate the conditions under which this assumption is exact.