NopMap wrote: > > A few days ago a new mass downloading application has appeared on my > server, already causing tile requests in the order of millions with up to > 600000 tiles for a single client. >
Mod_tile has some built-in QoS / throttling features, that might help alleviate the effects of large tile scrapers. There are three parameters in mod_tile.conf with which to control these. ModTileEnableTileThrottling Off ModTileThrottlingTiles 10000 1 ModTileThrottlingRenders 128 0.2 It throttles tile downloading per IP with a leaky bucket algorithm (with an initial bucket size in tiles and a tiles/second rate limit), which should catch applications even if they fake the UA string. Apart from tile serving, it also allows to throttle rendering requests at a different rate. I.e. every time mod_tile can't serve a tile from disk and has to ask renderd to render it, it will account it into a separate bucket. This should be particularly effective for low zoom tile scrappers and even out the use of the rendering queue to be more fair. The code has support for white listing certain IPs that shouldn't get throttled, e.g. in case the tile server is behind a proxy server, but there is no way to configure the white list yet other than in the code requiring a recompile. The throttling code also doesn't currently handle IPv6 though. I haven't heard anyone using these features in mod_tile yet, so although it should work I am not sure how well it is tested under production yet. Tile.openstreetmap.org uses a different (squid based) throttling mechanism, but the built-in way might be easier for smaller tile server installations. Kai -- View this message in context: http://gis.638310.n2.nabble.com/Paging-the-tile-server-admins-tp6308590p6309852.html Sent from the Developer Discussion mailing list archive at Nabble.com. _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
