Thomas A. Beavin

A framework for enforcing application policies in database systems

As database systems have grown in terms of scale and complexity, administration tasks have become increasingly difficult and time consuming. A scarcity of skilled database professionals has meant that human costs have begun to dominate the total cost of ownership (TCO) of a database system. Database vendors are under immense pressure to provide solutions that make their products easy to administer in areas such as problem diagnostics, monitoring, query tuning, access control and system configuration. To address this issue, we have built a framework that allows control over many administration operations via the use of policies. Users can uniformly define, manage and enforce policies to affect disparate aspects of the system. In our framework, policies are declarative constructs that are comprised of type, scope, condition and action. Policy groups cover query monitoring and tuning, query prioritization, system configuration, access control, report generation, etc. Policy scope defines the domain over which policies apply. Policy actions are performed if certain conditions are true. This framework has been fully integrated into DB2 for z/OS V9. Using detailed system performance evaluations, we report that enforcement of policies is largely a function of data-collection granularity. Under the setting for normal monitoring with minimal report, the overhead on system performance is very low (0.1%).