Improve performance in Edge Network preparation

[rustprooflabs]

Details

Colorado Roads network has been okay performance wise, running between 6 - 16 minutes on my laptop (while many browser tabs open, playing music, etc). This is with 1,192,543 input rows generating 2,538,882 output rows in edge network.

The Colorado osm.water_line data grinds to a halt in the initial_intersections step, even though it's only 464,807 input rows that outputs 519,597 edges.

[rustprooflabs]

What changed

I split the intersection detection into two steps. First combines all possible combos using bounding box, second performs actual intersection check and creates the blade. Splitting the queries fixed whatever issue was hanging up the water processing. I also removed unnecessary columns from intermediate temp tables, a few were geom columns that added unnecessary I/O load.

Timings from testing

Timing for the road network is well within the bounds I'm starting to expect on my laptop after the last few rounds of testing I've done. The waterway network is proportionately faster as expected due to its smaller network size.

Data is Colorado subregion downloaded from geofabrik today.

--    * 10 min 52 sec
CALL osm.routing_prepare_road_network();


-- CO Timings:
--    * 3 minutes 2 seconds
CALL osm.routing_prepare_water_network();