Combined Static and Dynamic Analysis for Effective Buffer Minimization in Streaming XQuery Evaluation

Effective buffer management is crucial for efficient in-memory and streaming XQuery processing. We propose a buffer management scheme which combines static and dynamic analysis to keep main memory consumption low. Our approach relies on a technique that we call active garbage collection and which actively purges buffers at runtime based on the current status of query evaluation. We have built a prototype system for a practical fragment of XQuery which employs our buffer management scheme. The experimental results demonstrate the significant impact of combined static and dynamic analysis on reducing main memory consumption and running time.