Fatores que influenciam no desempenho de sistemas de banco de dados

Abstract

Commonly, in the routine of organizations that use database systems (DB), the satisfactory performance of such systems is considered a crucial element to achieve success in the applications performed by them. Since such systems often provide information that contributes to the decision-making process, performing tuning activities on these systems is one of the primary functions of a database system administrator (DBA). The goal of tuning is to make the database system perform better, thereby ensuring satisfactory behavior consistent with the expected response time for the applications in question. In this context, the main objective of this paper is to study the factors that influence the performance of database systems. For this, we analyzed the process of building an operational database, starting with the conceptual data modeling phase, logical database design, physical database design and the subsequent use of these systems for extraction. For information purposes, the purpose of this process was to identify the existing tuning activities in each phase and the impact they had on the performance factor. Finally, after performing the theoretical study, an analysis was performed on a public database of the Transaction Processing Performance Council (TPC). This analysis sought to identify the influence that decisions taken in the early stages of database design had at the time of using these systems. For this purpose, queries were submitted for the extraction of information from this system without the application of tuning techniques,The query plans defined by the database management system (DBMS) to return such information were collected and stored. Afterwards, some concepts studied during the development of the present work were applied. Analyzes of the standard configuration of some DBMS parameters were performed. Regarding the hardware configurations of the machine used to perform this study, changes were made that included modifications to the logical and physical design of the database, after the modifications were submitted new queries to extract information from this system, the query plans. defined by the DBMS to return such information were compared with the consultation plans defined by the DBMS in the phase before the modifications, with this it was possible to analyze the practical application of some concepts studied during the development of the present work and validate the theoretical study re alized.