[OSM-dev] tips to reduce bulk tiles downloads ?

[sly (sylvain letuffe)]

> From the download pattern. Humans have a linear distribution of tile
> requests with most in zoom 14 and 15. Tile scrapers show an exponential
> increase with higher zoom levels. 

whaoo ! That shows you've gone far in tile scrapers activity analyse and it 
soon logical about "normal" human behavior.

Are you using mod_tile ? does it permit all that ? have you an other queue 
management/penalty/rate limiting software ?


> > file:///Applications/Install/83F78CDD-FB29-E011-854C-00237DE2DB9E/Install/
> > and user agent is : NativeHost
> > 
> 
> file: referrers hints at a local test installation somewhere. 

I had a private email from someone from the list who tried to search google 
for the strange "83F78CDD-FB29-E011-854C-00237DE2DB9E" string and found the 
culprit.
That's a windows phone apps claiming to provide "off live browsing" (wich I 
suppose means tile scraping ;-) ) for a lot of map providers among which mine 
is listed

> > Then comes (or alike):
> > "Dalvik/1.2.0 (Linux; U; Android 2.2.2; LS670 Build/FRG83G)"
> > 
> 
> The first looks fake, the second does not ring a bell except that it's
> likely something on Android. But a per zoom level limit should help.

After diging, il looks like a few android apps do implement tile scraping 
while other do implement only human browsing.
I found that mytrails as my renderer listed and also has a bulk scraping menu

> That seems rather random - I am having the most trouble with an Android app.
You are right, I just found one ;-)


-- 
sly
qui suis-je : http://sly.letuffe.org