A Systematic Performance Study of Object Database Management Systems

Many previous performance benchmarks for Object Database Management Systems (ODBMSs) have typically used arbitrary sets of tests based on what their designers felt were the characteristics of Engineering applications. Increasingly, however, ODBMSs are being used in non-engineering domains, such as Financial Trading, Clinical Healthcare, Telecommunications Network Management, etc. Part of the reason for this is that the technology has matured over the past few years and has become a less risky choice for organisations looking for better w'ays to manage complex data. However, the development of suitable application- or industry-specific benchmarks, based on actual performance studies, has not paralleled this growth. The research reported here approaches performance evaluation of ODBMSs pragmatically. It uses a combination of case studies and benchmark experiments to investigate the performance characteristics of ODBMSs for particular applications, following the successful use of this approach by Youssef [Youss93] for studying the performance of On- Line Transaction Processing (OLTP) applications for Relational Database Management Systems (RDBMSs). Six case studies at five organisations show’ that organisations consider a wide range of factors when undertaking their own performance studies or benchmarks. Furthermore, none of the studied organisations considered using any public benchmarks. Six current and derived benchmarks also highlight statistically significant performance differences between three major commercial products: Objectivity/DB, ObjectStore and UniSQL. These benchmarks indicate the suitability of the products tested for particular application domains. The research could not find any evidence at this time to support the concept of a generic or canonical performance workload for ODBMSs. This is demonstrated by the case studies and supported by the benchmark experiments. However, the research shows that performance benchmarks serve a very useful role in ODBMS evaluations and can help identify architectural and quality problems with products that would not otherwise be observed until significant application or system development was already in progress

Comparative Study between Relational Database System (RDBMS) and Object Relational Database System (ORDBMS) in Data Modelling and Database Languages

This paper presents comparative study between Relational Database Management System (RDBMS) and Object Relational Database Management System(ORDBMS). The objective are to develop two systems with different models; Relational Database Management System (RDBMS) and Object-Relational Database Management System (ORDBMS) and also to choose which model is better from user and designer's point of view in terms of data modeling. Several problems are being identified in order to know which model is better; Relational Database Model or Object-Relational Database. Model approach. Similarities and differences between the two models based on criteria such as data modeling are compared. This is to provide guidelines on which model users or designers to choose from based on different type of data that they wish to accommodate. The scope of research is limited to be on the development of RDBMS and ORDBMS. This project involves project planning, requirements gathering, requirements analysis, logical database design, physical database design and finally testing phase. Thus, for the data collection, a research and a survey has been conducted through readings and interviews. By developing this comparative study, this project is expected to be implemented in Admission and Registration Unit in which it can serve the better performance of database

A generalized system performance model for object-oriented database applications

Although relational database systems have met many needs in traditional business applications, such technology is inadequate for non-traditional applications such as computer-aided design, computer-aided software engineering, and knowledge bases. Object-oriented database systems (OODB) enhance the data modeling power and performance of database management systems for these applications. Response time is an important issue facing OODB. However, standard measures of on-line transaction processing are irrelevant for OODB . Benchmarks compare alternative implementations of OODB system software, running a constant application workload. Few attempts have been made to characterize performance implications of OODB application design, given a fixed OODB and operating system platform. In this study, design features of the 007 Benchmark database application (Carey, DeWitt, and Naughton, 1993 ) were varied to explore the impact on response time to perform database operations Sensitivity to the degree of aggregation and to the degree of inheritance in the application were measured. Variability in response times also was measured, using a sequence of database operations to simulate a user transaction workload. Degree of aggregation was defined as the number of relationship objects processed during a database operation. Response time was linear with the degree of aggregation. The size of the database segment processed, compared to the size of available memory, affected the coefficients of the regression line. Degree of inheritance was defined as the Number of Children (Chidamber and Kemerer, 1994) in the application class definitions, and as the extent to which run-time polymorphism was implemented. In this study, increased inheritance caused a statistically significant increase in response time for the 007 Traversal 1 only, although this difference was not meaningful. In the simulated transaction workload of nine 007 operations, response times were highly variable. Response times per operation depended on the number of objects processed and the effect of preceding operations on memory contents. Operations that used disparate physical segments or had large working sets relative to the size of memory caused large increases in response time. Average response times and variability were reduced by removing these operations from the sequence (equivalent to scheduling these transactions at some time when the impact would be minimized)

A storage and access architecture for efficient query processing in spatial database systems

Due to the high complexity of objects and queries and also due to extremely large data volumes, geographic database systems impose stringent requirements on their storage and access architecture with respect to efficient query processing. Performance improving concepts such as spatial storage and access structures, approximations, object decompositions and multi-phase query processing have been suggested and analyzed as single building blocks. In this paper, we describe a storage and access architecture which is composed from the above building blocks in a modular fashion. Additionally, we incorporate into our architecture a new ingredient, the scene organization, for efficiently supporting set-oriented access of large-area region queries. An experimental performance comparison demonstrates that the concept of scene organization leads to considerable performance improvements for large-area region queries by a factor of up to 150

Two Case Studies of Subsystem Design for General-Purpose CSCW Software Architectures

This paper discusses subsystem design guidelines for the software architecture of general-purpose computer supported cooperative work systems, i.e., systems that are designed to be applicable in various application areas requiring explicit collaboration support. In our opinion, guidelines for subsystem level design are rarely given most guidelines currently given apply to the programming language level. We extract guidelines from a case study of the redesign and extension of an advanced commercial workflow management system and place them into the context of existing software engineering research. The guidelines are then validated against the design decisions made in the construction of a widely used web-based groupware system. Our approach is based on the well-known distinction between essential (logical) and physical architectures. We show how essential architecture design can be based on a direct mapping of abstract functional concepts as found in general-purpose systems to modules in the essential architecture. The essential architecture is next mapped to a physical architecture by applying software clustering and replication to achieve the required distribution and performance characteristics

An introduction to Graph Data Management

A graph database is a database where the data structures for the schema and/or instances are modeled as a (labeled)(directed) graph or generalizations of it, and where querying is expressed by graph-oriented operations and type constructors. In this article we present the basic notions of graph databases, give an historical overview of its main development, and study the main current systems that implement them