Performance Issues in Adaptive Query Processing Fred Reiss U.C. Berkeley Database Group

What Is an Eddy? Query Optimizer Operator Output Static Plan

Adaptive Plan Eddy What Is an Eddy? Query Operator Tuple Pool Routing Policy Output

Eddy Performance Agenda Goal: Replace the query optimizer Mechanism –Make adaptivity cheap Policy –Simple and effective adaptive routing policy

Mechanism Goal: make adaptivity cheap Minimize overhead –Use batching to amortize decisions Offset overhead –Use the tuple pool to cluster similar tuples

Policy Goal: simplicity –Want a routing policy that handles a wide variety of situations Randomized routing –Lottery scheduling –Machine learning / statistical models Hybrid/adaptive routing –Use a static optimizer as a subroutine