The GCX System: Dynamic Buffer Minimization in Streaming XQuery Evaluation

In this demonstration, we present the main-memory based streaming XQuery engine GCX which implements novel buffer management strategies that combine static and dynamic analysis to keep main memory consumption low. Depending on the progress made in query evaluation, memory buffers are dynamically purged and minimized. In this demo, we show the various stages in evaluating a practical fragment of XQuery with GCX. We present the major steps in static analysis and demonstrate the mechanisms of dynamic buffer minimization. We apply our system to XML streams and demonstrate the significant impact of our approach on reducing main memory consumption and running time.