Showing papers in "Ibm Systems Journal in 1989"

Program understanding: challenge for the 1990's

Abstract: In the Program Understanding Project at IBM's Research Division, work began in late 1986 on tools which could help programmers in two key areas: static analysis (reading the code) and dynamic analysis (running the code). The work is reported in the companion papers by Cleveland and by Pazel in this issue. The history and background which motivated and which led to the start of this research on tools to assist programmers in understanding existing program code is reported here.

Multiple operating systems on one processor complex

Abstract: As large computing systems continue to grow in capacity and to offer improved price/performance, there is an increasing requirement to consolidate systems onto one processor complex. This paper describes the reasons why users need to run multiple operating systems today, provides a brief history of IBM's partitioning products, and introduces the Processor Resource/Systems Manager™, a machine feature on the IBM 3090 Model E and ES/3090™ Model S processors that provides users with a flexible and efficient capability to run multiple operating systems on a single processor complex.

System-managed storage

Abstract: In early 1988, IBM announced the Data Facility Storage Management Subsystem (DFSMS™), comprising functions in MVS/DFP™, other products in the Data Facility family, and RACF. This announcement constituted a major step in the realization of system-managed storage. The need for system-managed storage was established in the late 1970s and early 1980s, through growing customer requirements in the management of external storage space, performance, availability, and device installability within and across systems in these customers' installations. The concept of system-managed storage is an evolutionary one, culminating in a resource manager for external storage that separates the logical view of data from physical device characteristics, simplifies interfaces for the use and administration of storage, integrates the functions of storage management products, and provides a synergy of hardware and software functions to effect complex-wide management of external storage resources, as discussed in this paper.

An Arabic morphological system

Abstract: Nowadays, computers are used in every field in the Arab countries of the middle east. Software systems developed for the European languages are not convenient for the use of Arabic because of the nature of the language and its writing system. Problems arise when trying to use existing software systems, such as spell-checkers and business and office systems, with the Arabic language. These problems are attributable to the fact that the difference between Arabic and the European languages exists not only in character shapes and direction of writing, but also in language structure. In order to successfully use Arabic in software systems, we must, then, analyze the Arabic language word structure—that is, carry out a morphological analysis. Most of the written Arabic texts are nonvowelized, which may lead to ambiguity in meaning or mispronunciation. Moreover, vowelization cannot be avoided in many applications, such as speech synthesis by machines and educational books for children. A two-way Arabic morphological system (analysis/generation) capable of dealing with vowelized, semivowelized, and nonvowelized Arabic words was developed at the IBM Cairo Scientific Center. The system also has the ability to vowelize nonvowelized words. This system consists of three separate modules: computational lexicon, Arabic grammar model module, and analyzer/generator module. The grammar module contains, among others, morphophonemic and morphographemic rules formulated using the conventional generative grammar. Moreover, the developed system covers all of the Arabic language.

Data visualization in archaeology

Abstract: Archaeological field work produces vast amounts of three-dimensionally recorded data which can only be analysed using computers. Developments in data-visualization techniques are continually increasing the volume and complexity of data that can be studied meaningfully. In particular, three systems developed at the IBM United Kingdom Scientific Centre have been applied in a wide variety of archaeological situations: a graphics-database system called the Winchester Graphics System (WGS), IBMs IAX (Image Applications eXecutive) image processing system, and the WINchester SOlid Modelling system called WINSOM. It has been shown that these systems not only permit well-known problems to be answered in new and interesting ways but have freed archaeologists to explore previously undiscovered avenues of research. The techniques developed using these systems also have major implications for education and training.

A program understanding support environment

Abstract: Software maintenance represents the largest cost element in the life of a software system, and the process of understanding the software system utilizes 50 percent of the time spent on software maintenance. Thus there is a need for tools to aid the program understanding task. The tool described in this paper—program UNderstanding Support environment (PUNS)—provides the needed environment. Here the program understanding task is supported with multiple views of the program and a simple strategy for moving between views and exploring a particular view in depth. PUNS consists of a repository component that loads and manages a repository of information about the program to be understood and a user interface component that presents the information in the repository, utilizing graphics to emphasize the relationships and allowing the user to move among the pieces of information quickly and easily.

Application system/400 performance characteristics

Abstract: The operating system for Application System/400™ (AS/400™) provides an unprecedented breadth of function and system services in a single, integrated system. The majority of functions are implemented on top of an abstract, high-level machine interface in a hardware-independent manner, using many architectural characteristics normally associated with poor performance. Despite these architectural and functional traits of the operating system, the AS/400 exhibits excellent price and performance characteristics for commercial applications and is a competitive system in the mid-range commercial application arena. A number of design and optimization techniques, many of them unique or innovative, were incorporated into the AS/400 to achieve a combination of advanced design, function, and performance and are the main subjects discussed in this paper.

Advanced information management (AIM): advanced database technology for integrated applications

Abstract: The Advanced Information Management (AIM) project is currently one of the main activities at the IBM Scientific Center in Heidelberg. The main purpose of the project is to understand the database requirements and respective solutions for advanced integrated applications such as computer-integrated manufacturing and computer-integrated office. These application areas require an advanced database technology which is able to manage a large variety of data of various types in a consistent and efficient way. The underlying database technology should support not only simple numbers and simple tables used in business administration, but also large complex structured objects, including text, image, and voice data, in a uniform way. This paper describes the background, goals, and accomplishments of the AIM project. It also provides an overview of the design goals, the implementation, and the underlying concepts of AIM-P, an experimental database management system under development in the AIM project.

Evolution of the DASD storage control

Abstract: This paper identifies the major requirements and design points for storage controls and describes how these requirements have been met over time. It also describes the interplay of three critical components of a subsystem: hardware technology, microcode, and software.

The WINSOM solid modeller and its application to data visualization

Abstract: The IBM United Kingdom Scientific Centre's WINchester SOlid Modelling system (WINSOM) is a set-theoretic, constructive solid geometry (CSG) modeller based on recursive division techniques. It specializes in handling complex models and provides graphical facilities intended for engineering applications. This paper describes WINSOM and some of the many programs that are linked to it, and gives examples of their application to problems of data visualization.

Systems-independent file management and distribution services

Abstract: Applications universally require files to move from one location to another. Although different applications may use files differently, many of the files are of the same type. The identifying, fetching, moving, and storing functions are the same for all applications and can be most efficiently provided by a common process. Various applications can invoke the common process, which performs the required operations independently and notifies the appropriate applications when they are completed. In Systems Network Architecture (SNA) networks, the common process is an SNA/Distribution Services (SNA/DS) server defined by SNA/File Services (SNA/FS). The invoking applications are SNA/DS agents of various types. This paper describes the role of the agent in invoking the file transfer and the role of the SNA/FS server in fetching and storing the file. It also describes the SNA/FS architecture for uniquely naming files and data objects. One example of an SNA/DS agent that uses the SNA/FS server is the change management category of SNA/Management Services, described in another paper in this issue.

SPARKA: a knowledge-based system for identifying competitive uses of information technology

Abstract: The use of information and information technology (IIT) as a strategic tool to gain competitive advantage has become increasingly significant in recent years. Numerous examples of how firms are using IIT to improve their competitive positions are highlighted in both popular and academic literature. Although the potential competitive benefits of IIT are generally recognized by business and I/S executives, there is a great gap between recognizing such value and applying the technology effectively. To help bridge this gap, a group at the IBM Los Angeles Scientific Center has developed a knowledge-based system facilitator, called S*P*A*R*K. The system is designed to help business and I/S managers identify competitive applications of IIT to help them be creative in generating a range of IIT alternatives. This paper provides an overview of S*P*A*R*K, including the conceptual frameworks used for knowledge sources, the design philosophy, functions, and implementation approaches. Examples from a database of competitive applications of IIT are also presented to provide a flavor of the S*P*A*R*K facilitative processes.

DS-viewer—an interactive graphical data structure presentation facility

Abstract: DS-Viewer is a tool that is the result of a research project in data structure presentation within a program state. This tool addresses two distinct issues in this area: (1) to effectively present data structures themselves for a given program state and (2) to present groups of data structures and their interrelationships as described by their pointer definitions. Graphical presentations were developed to address these issues. For the data structure presentation, the user is provided a display window for any single data structure instance formatted with its fields and field values. Flexibility in display is provided by allowing the user a choice from the various value formats for each field. For groups of data structure instances, a graphical drawing space is provided in which pictures of these data structure instances and their interrelationships are drawn as blocks and arrows. The computer assists the user in drawing such a picture by describing its components, allowing the user to choose which to draw and to construct as much of the picture as desired.

Local-area distributed systems

Abstract: Advances in computing and networking have led to the use of local-area distributed systems. The following are example configurations: workstations and file servers, multiple computers that present the image of a single computer, and heterogeneous workstations and mainframes that cooperate loosely. The paper focuses on the system software. It first discusses the forces leading to distributed systems and the obstacles to realizing the full value of the systems. Discussed also are common current uses of local-area distributed systems. Concepts and models are introduced. Requirements for user and program interfaces and for administration are presented, as well as major design attributes and design issues. Systems that represent the main approaches are described.

Technical note—engineering and scientific subroutine library release 3 for IBM ES/3090 vector multiprocessors

Abstract: This technical note should be read in conjunction with the paper by McComb and Schmidt 1 which describes the Engineering and Scientific Subroutine Library through Release 2. In this technical note, which is an addendum to that paper, we briefly describe some of the new features in Release 3 and indicate some of the techniques used to optimize vector and parallel performance.

Systems overview of the application system/400

Abstract: This paper describes IBM's recently available general-purpose midrange computers—the Application System/400™, the basic intentions of the product, the significant factors setting forth system requirements, the primary design themes incorporated in the implementation of those requirements, and a description of some of the key system components. However, the paper is not intended to provide a complete system description.

Technical note—computer sculpture

Abstract: This technical note illustrates the graphic techniques used to generate the cover of this issue. It should be read in conjunction with the paper on WINSOM 1 which describes the computer program used to generate the computer sculptures.

Enterprise Systems Architecture/370: an architecture for multiple virtual space access and authorization

Abstract: The Enterprise Systems Architecture/370™ provides a significant step in the IBM System/370 evolution by providing new capabilities for virtual addressing and program linkage across multiple address spaces. This paper reviews the evolution that led to this advance and illuminates the goals, such as eliminating growth constraints and improving security, integrity, reliability, and performance, that have guided it. The major architectural capabilities are discussed, along with the system environments in which they are useful. The rationale for design choices is presented and related to issues of performance, access authorization, and constraints relief.

MVS data services

Abstract: The IBM Enterprise Systems Architecture/370™ vastly increases the potential virtual addressability available to both system and application programs. The I/O model and the application model of permanent data are discussed to illustrate how large virtual addressability can be used to simplify application programs and improve performance. New MVS services that exploit the architecture are described. Also described are data window services, which are callable from high-level languages and provide the capability to manage very large permanent and temporary objects in virtual storage.

Concurrent computing by sequential staging of tasks

Abstract: Described is a new approach to parallel formulation of scientific problems on shared-memory multiprocessors such as the IBM ES/3090 system. The class of problems considered is characterized by repetitive operations applied over the computational domain D. In each such operation, some fields of interest are extrapolated or advanced by an amount of Δτ. The integration variable τ may be time, distance, or iteration sequence number, depending on the problem under consideration. An extensively studied approach to parallel formulation of such computational problems is based on domain decomposition, which attempts to partition the domain of integration into many pieces, then construct the global solution from these local solutions. Thus, domain decomposition methods are confined to D alone at a single τ level. An inquiry into the possibilities of formulating parallel tasks in τ, or more significantly in the D × τ domain, opens up new horizons and untapped opportunities. The aim of this paper is to detail an approach to exploit this τ domain parallelism that will be referred to as sequential staging of tasks (SST). Concurrency is realized by means of ordering the tasks sequentially and executing them in a partially overlapped or pipelined manner. The SST approach can yield remarkable speedup for jobs requiring intensive paging I/O, even when a single processor is available for executing multiple tasks. Noteworthy features of the SST method are demonstrated and highlighted by using results obtained from computer experiments performed with a numerical solution method of the Poisson equation and migration of seismic reflection data.

Design, test and validation of the application system/400 through early user involvement

Abstract: The Application System/400™ (AS/400™) is the culmination of a development effort requiring seven million lines of code. Key challenges to its development were those of ensuring that the system had been designed correctly and thoroughly tested, that IBM Business Partners were ready for its introduction together with their applications, and that IBM marketing representatives and systems engineers were trained and knowledgeable on the system. This paper discusses how these challenges were met through the involvement of customers, Business Partners, vendors, and systems engineers in the development of the AS/400 system so as to positively affect its design and quality.

VM/XA SP2 minidisk cache

Abstract: Given the growing disparity between CPU power and the speed of secondary storage, a data cache exploiting large processor storage has the potential to improve response time dramatically in many situations. The VM/XA SP2 minidisk cache facility, the result of research activity on the characteristics of interactive file-system activity, uses expanded storage to cache input/output to minidisks on the Conversational Monitor System. The size of the cache is dynamically adjusted by an arbitration process to optimize system performance. Several other functions improve the performance of the cache during periods of unusual I/O loads.

Large systems and enterprise systems architecture

Abstract: A number of diverse factors have influenced the development of IBM's Enterprise Systems Architecture. They range from the compatibility and migration considerations so important for preserving customer investments in existing applications and data, to new functional and capacity requirements of our customers, to the implications of emerging technologies and the projection of these into the systems environments of the future. This paper provides an introduction to a collection of technical papers in this issue describing the ESA/370™ facilities. Its purpose is to convey a broad perspective on important factors that will influence the large-systems environment of the future, and to relate those factors to the key elements of the ESA/370 architectural enhancements. It does not attempt to address all of the considerations leading to the development of ESA/370, nor discuss the new features in any depth. Detailed discussion of the specific features, facilities, and design considerations of ESA/370 will be found in other papers in this issue.