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I am currently working on a planning system for cycling, walking, sailing, etc. It is based on both a fixed network and a full OSM network. There is a web app for the planning of routes and a mobile app for the navigation of these routes.

Among others i have used the following tools: postgresql, postgis, pgrouting, QGIS, Open Jump, Google Maps, Osmdroid, leaflet.

Atm i am interested in fast routing solutions that allow me to route realtime on larger OSM datasets (>100K ways).


Nov
16
comment How can I optimize pgrouting for speed?
Délawen, i have also been thinking about your first idea (ST_Buffer) and foresee the same problem. The advantage however could be 2 way: the dataset is smaller and thus faster and as more of the processing is being done in Postgresql you have ways again to optimize it. Atm i am using Ubuntu 11 where postgresql 8.4 is the latest version.
Nov
15
comment How can I optimize pgrouting for speed?
No, i even had to look it up on Wikipedia. The difference between our goals seems to be that you have to determine a best route for your customers and my customers get a totally free hand in choosing their route (i do not yet assume anything about their wants)
Nov
15
comment How can I optimize pgrouting for speed?
I have read parts of the book you recommend. My dataset is still small enough to fit entirely into memory so i think disk performance shouldn't be a bottleneck (i will better check my resources when testing to confirm this). I think Postgresql only comes into play in the pgrouting process when it does a simple select * from table to feed the C Boost library with row/tuples to perform the real search ((can someone confirm this) so i fear that there isn't much to gain in Postgresql itself. Your answer seems very good for Postgresql performance but maybe not so for pgrouting specific performance.
Nov
15
comment How can I optimize pgrouting for speed?
Don't you get weird results if someone wants to go from 1 zone to the next but they get routed through their centroids? Or do you only use this when the zones are further apart? Your solution makes the most sense if customers want to get fastest from A to B, but in my case i have to deal with customers who want to walk,cycle,etc for leisure and would like to pick unique routes and not be forced to go via the standard route.
Nov
15
comment How can I optimize pgrouting for speed?
I allow free search atm, so i don think i can assume much for sub routes. Also I am caching the result of searches of the last x minutes, but that doesn't help me for new searches. I have a feeling that A* on this size should still be really fast as long as i can keep the entire graph static in memory. There must be people who route this way on a whole country who know how to improve the performance.
Nov
15
comment Measuring distance between points along a river system
I assume you have a multilinestring? You could create a graph based on all your data points and use shortest_path algorithms on that mini graph. Or you could cut the river in two at the fork and work with that. Then your points should be sequential again.
Nov
15
asked How can I optimize pgrouting for speed?
Oct
29
comment ST_Distance versus ST_Distance_Spheroid?
Does this mean that if you use lat lon projection, A* will also be using degrees for its heuristic function? And even worse (as i had lengths of edges in meters) that A* will effectively become Dijkstra's algorithm?
Oct
28
comment ST_Distance versus ST_Distance_Spheroid?
I will mainly cover the area of Netherlands and parts of northern Germany. Maybe i should use RD_New? I do not need to be very precise. Less than 3-5% would be ok for me i guess.
Oct
28
accepted ST_Distance versus ST_Distance_Spheroid?
Oct
28
comment ST_Distance versus ST_Distance_Spheroid?
Is ST_Distance used on spherical mercator (900913) geometry just as precise as using ST_Distance_Spheroid on WGS 84? And i conclude from your answer that my decision to do operations on Spherical Mercator instead of WGS 84 if speed is a necessity is a good one?
Oct
28
revised ST_Distance versus ST_Distance_Spheroid?
added 21 characters in body
Oct
28
asked ST_Distance versus ST_Distance_Spheroid?
Oct
25
revised How to route over (partial) edges in pgrouting?
edited body
Oct
25
revised How to route over (partial) edges in pgrouting?
added 2 characters in body
Oct
25
revised How to route over (partial) edges in pgrouting?
added 3 characters in body
Oct
25
asked How to route over (partial) edges in pgrouting?
Oct
17
awarded  Talkative
Sep
20
asked Is there an open source directions webclient for pgRouting like the directions API from Google?
Sep
15
comment Where can i find free mapnik map styles with focus on waterways?
@Igor, yes i have and will do if i can't find it somewhere and my own attempts don't match my goal.