Evaluating the Effect of Multi-Tenancy Patterns in Containerized Cloud-Hosted Content Management System

Multi-tenancy in cloud computing describes the extent to which resources can be shared while guaranteeing isolation among components (tenants) using these resources. There are three multi-tenancy patterns: shared, tenant-isolated and dedicated component patterns. These patterns have not previously been formally specified. In order to create a precise definition and verify each pattern, we formally specify each pattern using the Z language. To validate the interpretation of our formal description, We empirically evaluate each pattern using the data-tier of a cloud hosted distributed content management application, WordPress, deployed in a Docker container. Experimental results show that the dedicated pattern successfully managed larger numbers of tenants with fewer unhandled request errors. The shared and tenant isolated patterns exhibited larger number of unhandled request errors when the number of tenants increased. We present a selection algorithm to choose suitable multi-tenancy pattern for cloud deployment of content management system.