User:Roland.olbricht

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 interested in Public Transport. Thus, I'm mapping on the public transport network at my home city Wuppertal.

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.