tailieunhanh - Research Directions in Object-Oriented Database Systems

Moreover, typically, previous work investigated en- forcing a given resource partitioning of a single re- source, within a single software tier at a time. In our own previous work in the area of dynamic parti- tioning, we have investigated either partitioning mem- ory, through a simulation-based exhaustive search ap- proach [24], or partitioning storage bandwidth, through an adaptive feedback-loop approach [23], but not both. In this paper, we consider the problem of global resource allocation, which involves proportioning the database and storage server caches, and the storage band- width among applications, according to overall perfor- mance goals. To achieve this, we focus on building a simple performance model in order to guide the. | Research Directions in Object-Oriented Database Systems Won Kim Microelectronics and Computer Technology Corporation 3500 West Balcones Center Drive Austin Texas 78750 ABSTRACT The set of object-oriented concepts found in object-oriented programming languages forms a good basis for a data model for post-relational database systems which will extend the domain of database applications beyond conventional business data processing. However despite the high level of research and development activities during the past several years there is no standard object-oriented data model and criticisms and concerns about the field still remain. In this paper I will first provide a historical perspective on the emergence of object-oriented database systems in order to derive a definition of object-oriented database systems. I will then examine a number of major challenge which remain for researchers and implementors of object-oriented database systems. 1. INTRODUCTION The rapidly increasing use of object-oriented concepts in various components of software technology has naturally necessitated object-oriented database systems. There is a flurry of activities to build and market object-oriented database systems RELE89 KIM90d . There are several commercial products in various stages of readiness. There are at least a dozen industrial research projects around the world to prototype object-oriented database systems and object-oriented database systems are also under development in a comparable number of university laboratories. Permission to copy without fee all or part of this matertial is granted provided that the copies are not made or distributed for direct commercial advantage the ACM copyright notice and the title of the publication and its date appear and notice is given that the copying is by permission of the Association for Computing Machinery. To copy otherwise or to republish requires a fee and or specific permission. 1990 ACM 089791-352-3 90 0004 0001 1 Despite all .