We have built an OSM Tile Server following the instructions at


We have imported planet_latest.osm.pbf. Our server renders very slowly at low zoom levels (especially 1 -10) and increases in speed as the zoom levels increase.

We believe this is to be expected, but could someone please explain why the rendering speeds vastly differ depending on the zoom level?


1 Answer 1


You have to consider that the tiles are not built from your database only.

For low zoom levels, coastline shapefiles and Natural Earth shapefiles are used, and osm data is added from about zoom level 5 onwards. There is a special roads layers with simplified geometries for lower zoom levels as well.

The rendering time is a balance of database query time and tile storage time. From my experience, zoom level 9 is finished in the shortest time for a given area, but that may differ between OS and Postgis/mapnik versions.

  • Thanks for the reply. We had not even considered the coastline data. Jan 22, 2015 at 18:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.