Empowering a Relational Database with LSD: Lazy State Determination

• Autor(a) principal: Parreira, Thales Vinícius Alves
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/151108
• topic: Concurrency Control; Relational Databases; Lazy State Determination; Java Database Connectivity; Transactions; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Eletrotécnica, Eletrónica e Informática

Computer systems are a part of today’s most common activities and, more often than not, involve some type of interaction with a database. In this scheme, databases play a big role, where even small operational delays could cost millions to big tech companies. It is then, of utmost importance that such systems are responsive and adapt automatically to different types of workload. To this date, Relational Database Management System remain the most popular database type, which allows the executing of concurrent transactions with Atomicity, Consistency, Isolation and Durability guarantees. Enforcing such properties requires strict control over the execution of transactions. However, maintaining such properties and controlling the transactions’ concurrency may hamper performance of the system, being this specially the case when database contention is high. Motivated by such behavior, we propose the lazy evaluation of database SQL queries — using Futures/Promises and Java Database Connectivity (JDBC) — by empowering a relational database with Lazy State Determination (LSD). This novel Application Programming Interface (API) allows delaying operations to the commit time, which in the end reduces the transaction window where conflicts may occur. We observed that, by introducing our implementation of a JDBC-LSD driver, in high contention scenarios the throughput increased by 50% and latency reduced by 40%.