I was able to resolve the issue that blocked the two aggregate queries: sum (q02) and max (q03). The following queries show a similar story as the previous filter queries.
Query q02 (50mb) --------------- 0m36.713s Saxon 1m16.764s VXQuery xml 1m21.594s VXQuery xml.gz Query q02 (500mb) --------------- 2m11.029s Saxon 8m03.735s VXQuery xml 8m46.822s VXQuery xml.gz Query q03 (50mb) --------------- 0m33.280s Saxon 1m00.807s VXQuery xml 1m03.500s VXQuery xml.gz Query q03 (500mb) --------------- 1m58.784s Saxon 10m01.340s VXQuery xml 10m26.236s VXQuery xml.gz Throughput: Saxon (both queries) ~1.4 mb/s (50mb) to ~3.8 mb/s (500mb) VXQuery (q02) ~0.6 mb/s VXQuery (q03) ~0.8 mb/s
