Consistent and Efficient Application Caching

• Autor(a) principal: Mendes, Francisco Ramos de Deus
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/163560
• topic: Application caching; Consistency; Concurrency; Invalidation; Transparent caching; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Eletrotécnica, Eletrónica e Informática

Application caching has become extremely popular and vital to today’s Web applications and services, becoming a core component of these systems. Application caching consists of integrating a caching layer into the existing application and storing data and computation results from the database. It significantly improves performance by producing faster responses and reducing overall system load. However, while this level of caching provides better latency and scalability for the applications and services that use it, there are some complex challenges to consider. One of the primary challenges is to guarantee that the data in the cache remains consistent with the data stored in the database when concurrent requests are issued to the application. The integration of mechanisms in the application to ensure this consistency can be complex and is often overlooked, leading to the return of stale data or the unnecessary invalidation of still up-to-date data from the cache. If this issue remains unresolved, it leads to consistency or performance problems for the application, ultimately defeating the purpose of using an application cache. In this dissertation, we propose a system named ClearCache, which addresses this consistency problem. It was designed as an integrated library that can be used in applications that make use of MongoDB as their database, and it includes the logic required to write to and access data from a Redis cache instance automatically. Through the use of timestamps and Redis functionalities, it transparently manages the consistency between the database and cache layers. Lastly, we present an experimental evaluation, where the results showthat ClearCache enables better performance for applications that use it, reducing latency and increasing performance. In addition to its efficiency, it is also simple to use