Platform-as-a-Service Architecture for Performance Isolated Multi-tenant Applications

Software-as-a-Service (SaaS) often shares one single application instance among different tenants to reduce costs. However, sharing potentially leads to undesired influence from one tenant onto the performance observed by the others. This is a significant problem as performance is one of the major obstacles for cloud customers. The application does intentionally not manage hardware resources, and the operating system is not aware of application level entities like tenants which makes the performance control a challenge. In case the SaaS is hosted on a Platform-as-a-Service (PaaS), the SaaS developer usually wants to control performance-related issues according to individual needs, and available information is even more limited. Thus, it is difficult to control the performance of different tenants to keep them isolated. Existing work focuses on concrete methods to provide performance isolation in systems where the whole stack is under control. In this paper we present a concrete PaaS enhancement which enables application developers to realize isolation methods for their hosted SaaS application. In a case study we evaluated the applicability and effectiveness of the enhancement in different environments.