Multiprogramming System Research Articles

A multiprogramming system for process control

This paper describes an operational small computer multiprogramming system developed for the control of the Stanford Two Mile Linear Accelerator (SLAC). The system has many features of larger systems such as dynamic memory allocation and interprocess control, but does not have to handle typical batch type jobs which need large arrays and many other system resources. This difference results in a drastic reduction in the complexity of both design and implementation. The accelerator control problem is discussed in terms of what requirements are imposed on the system by the environment. Then the basic subsystems are described with sufficient examples to show the reader other areas where such a system may be applicable.

A study of storage partitioning using a mathematical model of locality

Both fixed and dynamic storage partitioning procedures are examined for use in multiprogramming systems. The storage requirement of programs is modeled as a stationary Gaussian process. Experiments justifying this model are described. By means of this model dynamic storage partitioning is shown to provide substantial increases in storage utilization and operating efficiency over fixed partitioning.

Asymptotic Service System Output, with Application to Multiprogramming

In a multiprogramming computer system modeled as a cyclic queue the number of program segments completed at the CPU in a period of time is discussed. It is shown that this number is approximately normally distributed as the time period becomes long. Parameters of the normal distribution are determined. Numerical examples illustrate the results.

The design of the Venus Operating System

The Venus Operating System is an experimental multiprogramming system which supports five or six concurrent users on a small computer. The system was produced to test the effect of machine architecture on complexity of software. The system is defined by a combination of micro-programs and software. The microprogram defines a machine with some unusual architectural features; the software exploits these features to define the operating system as simply as possible. In this paper the development of the system is described, with particular emphasis on the principles which guided the design.

OS6--An Experimental Operating System for a Small Computer. Part 1: General Principles and Structure

This paper is a description of a simple operating system, which runs in a virtual machine (implemented on a real machine by an interpreter). OS6 copes with only one user at a time, and is not a multi-programming system: many major problems associated with large operating systems have therefore been avoided or considerably simplified. It nevertheless has several features of interest, including the fact that it is written almost entirely in the high-level language BCPL. The most important single feature, however, is the hierarchical nature of its control structure, which avoids the need for a special job-control language.

A study of storage partitioning using a mathematical model of locality

Both fixed and dynamic storage partitioning procedures are examined for use in multiprogramming systems. The storage requirement of programs is modeled as a stationary Gaussian process. Experiments justifying this model are described. By means of this model dynamic storage partitioning is shown to provide substantial increases in storage utilization and operating efficiency over fixed partitioning.

The design of the Venus operating system

The Venus Operating System is an experimental multiprogramming system which supports five or six concurrent users on a small computer. The system was produced to test the effect of machine architecture on complexity of software. The system is defined by a combination of microprograms and software. The microprogram defines a machine with some unusual architectural features; the software exploits these features to define the operating system as simply as possible. In this paper the development of the system is described, with particular emphasis on the principles which guided the design.

Control variable methods in the simulation of a model of a multiprogrammed computer system

AbstractOne approach to the evaluation of the performance of multiprogranmed computer systems includes the development of Monte Carlo simulations of transitions of programs within such systems, and their strengthening by control variable and concomitant variable methods. An application of such a combination of analytical, numerical, and Monte Carlo approaches to a model of system overhead in a paging machine is presented.

A Quantitative Rule for The use of Resources in a Multiprogrammed ComputerSystem

AbstractThe computer has been used extensively to help solve problems in management science, but little has been done in the opposite direction. This paper describes an application ofquantitative techniques to improve the throughput of a computer system.One of the trendsin large-scale computer operations is towards multiprogrammed systems. Here the adjectivemultiprogrammed is meant to imply that two or more jobs simultaneously occupy the main memory of the computer and share resources such as the centra! processor, machine operators, and input/output devices. Under such a parallel configuration, any hardware and/or software change that is geared to speed up the completion of a particularjob may have over-compensating detrimental effects on the other jobs that reside in parallel with the one under consideration.In this paper, a quantitative rule is developed, based on the criterion of maximizing total throughput of jobs, to decide whether or not a proposed change is desirable. Careful consideration is give...

Erratum to: A six-channel PDP-8 interface for nerve impulse data; Zoroaster: A multiprogramming system for psychological research

Erratum to: A six-channel PDP-8 interface for nerve impulse data; Zoroaster: A multiprogramming system for psychological research

System Deadlocks

A problem of increasing importance in the design of large multiprogramming systems is the, so-called, deadlock or deadly-embrace problem. In this article we survey the work that has been done on the treatment of deadlocks from both the theoretical and practical points of view.

Models and algorithms for deadlock in computer systems

A major problem in multiprogramming systems in which processes may wait for resources is the prevention or detection of deadlocks. Deadlock is the situation in which one or more processes are blocked forever waiting for resources which can never become available. This problem has received considerable attention recently (see for example [1, 3, 4, 5, 6, 8, 9].) This note introduces a conceptually simple graph model; this model unifies much of the previous work on deadlock, leads to fast deadlock detection and prevention algorithms, and is suitable for teaching purposes.

Zoroaster: A multiprogramming system for psychological research

The development of a multiprogramming system for psychological research was undertaken on a PDP-9 computer with 8k memory. The needs of the users and the time demands on the computer raised several important questions: (1) Can a practical timesharing system be developed with only 8k memory? (2) Can critical timing functions be maintained? (3) Can easy access be provided (e.g., Fortran) to all experimental devices? (4) Can a system be designed which will take advantage of and be compatible with most of the standard DEC-provided software (e.g., Fortran compiler, loader)? The system was successfully developed by using a rapid within-core swapping technique, standard I/O routines, many general-purpose handlers and subroutines, and fully utilizing available core.

Present Status of the Software for Computer Control in the CERN ISR Project

A multi-programming system has been written to schedule the various application programs and to exploit the hardware attached to the CERN ISR control computer system. This paper describes certain features of the system, in particular those that concern its operation, as well as a synopsis of the applications.

Modeling for computing center planning

A probability-based, theoretical model of a multiprogrammed computing system is suggested for planning future computing center requirements. Validation of the planning model is attempted with respect to the theoretical model and applications to short-range and long-range planning.

B70-4 Theory of Scheduling

Scheduling and resource allocation have come to the forefront of the problems that confront the designers of computer systems. This is particularly true in time-sharing, multiprogramming, and real-time systems, but it is also the case for somewhat less sophisticated systems due to problems created by disk accessing. Theory of Scheduling is a very readable treatment of some of the "classical" solutions to scheduling problems, as well as some heuristic ad hoc approaches that are suitable in particular computer environments. The operating systems designer should not consider this book as the panacea for all of his ills, however, because the methodology that is given for solving his scheduling problems may be unsatisfactory in the context in which he chooses to use it. For example, in a real-time system the scheduling algorithm must satisfy constraints on maximum computation time which are not necessarily satisfied by the algorithms described in the text.

Optimization of Memory Hierarchies in Multiprogrammed Systems

The optimization of memory hierarchy involves the selection of types and sizes of memory devices such that the average access time to an information block is a minimum for a particular cost constraint. It is assumed that the frequency of usage of the information is known a priori. In this paper the optimization theory for a single task or program is reviewed and it is extended to a general case in multiprogramming when a number of tasks are executed concurrently. Another important extension treats the case when memories are available only in indivisible modules. Comparisons with conventional methods of solution as well as computational experience on the multiprogrammed and modular cases are given.

The nucleus of a multiprogramming system

This paper describes the philosophy and structure of a multi-programming system that can be extended with a hierarchy of operating systems to suit diverse requirements of program scheduling and resource allocation. The system nucleus simulates an environment in which program execution and input/output are handled uniformly as parallel, cooperating processes. A fundamental set of primitives allows the dynamic creation and control of a hierarchy of processes as well as the communication among them.

Combined interactive computer measurement and automatic classification of human chromosomes.

A computer system to both measure and classify human chromosomes with good accuracy compared to manual methods is described. Using a 35-mm photomicrographic negative, the system, while measuring the chromosomes automatically, requires a human operator’s interaction for about 15% of the chromosomes. Results for an initial 45 spreads are given. Using the interactively measured arm lengths and arm areas, the system classified over 99% of the chromosomes correctly into 10 classes without any assistance; two chromosomes, or 0.1% of the initial sample, were misclassified (from group D to E). For the remaining 1%, interaction after classification was requested by the computer, and, with the information available to the operator, a correct classification can be made in these cases by him. The system uses a computer-controlled flying spot scanner connected to a medium-size general purpose computer, an IBM 360 Series, Model 30, and takes 25 min per spread. An annual capacity of 7500 analyzed spreads will be available in 1971 after installation of an RCA Spectra 70/46, operating under a multi-programmed system, in October 1970. Applications for the system may depend on cytogeneticists exploiting its advantages and avoiding the drawbacks described.

Design and implementation of a clinical data management system

Increasing activity in the use of computers for acquisition, storage, and retrieval of medical information has been stimulated by the growing complexity of medical care, and the needs for standardization, quality control, and retrievability of clinical data. Criteria for the design of a clinical data management system include flexibility in its interface with its environment, the capability of handling variable length text string data, and of organizing it in tree-structured files, the availability of this data to a multi-user environment, and the existence of a high-level language facility for programming and development of the system. The scale and cost of the computer configuration required to meet these demands must nevertheless permit gradual expansion, modularity, and usually duplication of hardware. The MGH Utility Multi-Programming System (MUMPS) is a compact time-sharing system on a medium-scale computer dedicated to clinical data management applications. A novel system design based on a reentrant high-level language interpreter has permitted the implementation of a highly responsive, flexible system, both for research and development and for economical, reliable service operation.