[OSM-talk] Downloading lots of tiles from tile.openstreetmap.org
osm at bowvalleytechnologies.com
Sat Nov 10 05:44:31 GMT 2007
Jason Reid wrote:
> Jon Burgess wrote:
>> We don't have any specific terms of service for downloading tiles from
>> tile.openstreetmap.org and people often download thousands of tiles with
>> scripts. Quite often people often submit requests for completely invalid
>> tile co-ordinates. A couple of examples from this evening:-
>> [09/Nov/2007:20:15:35 +0000] "GET /mapnik//12529/11592.png HTTP/1.1"
>> * The zoom level is missing from this request.
>> [09/Nov/2007:22:40:08 +0000] "GET /20/528358/383233.png HTTP/1.1"
>> * This client is trying to fetch zoom=20 tiles which have never existed.
>> The highest zoom for the Mapnik layer is 18
>> The examples have been repeated 100,000+ times from 2 IP addresses
>> today. I don't want to restrict people from downloading lots of tiles
>> but if people keep submitting bad requests then it is a complete waste
>> of bandwidth and server resources.
>> If you write tools to grab lots of tiles please at least try to ensure
>> you are fetching valid tiles URLs!
> One thing that I will check is if any are coming from the newest release
> of Maemo-Mapper for the Nokia tablets, the 2.0.3+ release increased the
> maximum zoom levels so its possible that it may be trying to fetch
> beyond what we have. I will test and confirm later tonight once I find
> where I left my N800.
Alright, I can confirm that Maemo-mapper will try to access zoom 19 and
21 tiles if you zoom into the maximum amount that it allows. I will
contact the author of Maemo-mapper and bring it to his attention. I can
see that there may be a large number of requests from this, as its not
uncommon to preload huge areas at once (its easy to ask for it to
preload over 500mb of tiles, which would likely include a lot large
percentage of tiles that are beyond our rendering limit).
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