Policy-based Management of a JDBC Connection Pool

Managing the communication between an application server and a back-end database is essential for scalability and crucial for good performance. The standard mechanism uses a variable-sized pool of connections, but typical application servers provide very rudimentary, implementation-centric, pool control mechanisms. This requires administrators to manually translate service level specifications into the pool control mechanism, and adjust these as the load or machine configurations change. We describe the use of a resource management framework to automatically control connection pool parameters based on externally supplied policies.This simplifies the connection pool implementation while at the same time allowing a variety of policies to be applied, including policies that automatically adapt to changing circumstances.

The implementation of two distinct policies are discussed and performance measurements are reported for a contemporary synthetic application benchmark.