|Roland.olbricht commits code to OpenStreetMap under the name roland.|
Hello, my name is Roland.
My eMail adress is roland.olbricht (at) gmx.de .
For mapping I use the username "drolbr".
I'm also running the Overpass API server to enable anybody doing complex spatial queries on the OSM data.
Furthermore, I've done some work on country boundaries a year ago: this means the introduction of the 12-nm nautic border for the United Kingdom.
Some benchmarks for Overpass
A recent performance test of JXAPI inspired me to compare the results to the current servers:
|query||best JXAPI||Overpass at Hetzner (w/ meta)||Overpass at Rambler (w/o meta)|
|map?bbox=11.54,48.14,11.543,48.145||27 s||2 s||2 s|
|*[bbox=11.54,48.14,11.543,48.145]||< 1 s||2 s||1 s|
|*[amenity=library][bbox=-0.57,51.24,0.31,51.75]||2' 11 s||22 s||8 s|
|node[power=generator]||53 s||> 3'||46 s|
|*[amenity=parking][capacity:disabled=*][bbox=-0.57,51.24,0.31,51.75]||-||9 s||11 s|
|*[amenity=parking][bbox=-0.57,51.24,0.31,51.75]||6' 44 s||19 s||9 s|
|*[waterway=sluice_gate]||5 s||3 s||1 s|
|*[bdad6d21a=1378b02bc]||< 1 s||1 s||< 1 s|
|*[power=generator]||2' 47 s||> 3'||1' 10 s|
|map?bbox=-124,49,-123,50||2' 23 s||1' 33 s||1' 37 s|
"> 3" indicates that the query has timed out. The "map?..." queries don't support meta data.
- JXAPI can now be tuned to have an acceptable performance. Congratulations.
- The meta data is rather expensive. Serving it makes the query two to three times slower.
- The disk speed is in both systems essential for the database performance.
- The focusing of Overpass API is still visible: Queries with a not too large bbox are delivered much faster while queries with global distribution don't give much advantage.
- The three-minute-timeout of the XAPI interface imposes a rather tight limit on the size of the queries.