Tenant Oriented Lock Granularity Adjustment Strategy in the Shared Storage Multi-tenant Database
SaaS is a perfect technology to achieve scale economy. It uses multi-tenant to allow database to share storage but with irregular load, untraceable transaction characteristics and so on. TOL mechanism provides one granularity between the upper coarse-grained granularity and the lower finegrained granularity for each tenant. But the granularity may not be the most suitable. We define the cluster method and the diffusion method to support the granularity adjustment for a single tenant. Cluster is to make the granularity adjust towards coarser while diffusion gains opposite effect. Because TOL takes advantage of data distribution in multi-tenant database, we combine several aspects when the adjustment strategy is established, including basic table plus extension table and transactions feature. It focuses on locating a more suitable granularity size for one tenant between coarse-grained and fine-grained. In addition, we give experiments indicating that the lock granularity adjustment method is feasible and the adjustment strategy is effective.