[OSM-dev] Mapnik's speed rendering slow ?

[sylvain letuffe]

Hi there,

I'have set up a tiles server based on mapnik that I plan to use (for now) for 
France only.
( Very good wiki page explaining that)
My setup is : debian etch 64/mapnik 0.5.1/postGIS/generate_tiles.py
with a quite common machine : dual core 2.5GHZ / 2Go RAM

After much fighting I finaly made it work, and I am happy on all aspects, but 
speed.

While the Mapnik at openstreetmap.org does the rendering (until level 18 if I 
see it well) in something like around ~24 hours, I am currently doing it for 
france (600Mo of osm data) until level 14 at a poor ~15 hours time

Unless the server over there is a martian one clocked at 10^16 Hz, I think I'm 
doing something wrong, but what ?

I was searching on the wiki/doc at mapnik but didn't find tips for that

The only thing I changed in generate_tiles.py is :
minZoom = 5
maxZoom = 16
bbox = (-4, 42.0,8,50.0)
render_tiles(bbox, mapfile, tile_dir, minZoom, maxZoom)

Symptoms to help :
- The CPU is fed up at 100% ( load 1.00)
- The memory is almost unused (5Mo for postgres !! 60Mo for generate_tiles.py)
- The disk is unused
- A tile takes ~0.5s to be generated
- Severall thousand of "Empty Tile" messages appears during the process, while 
still taking ~0.5s
Does this benchmark looks okay ?

Thanks for help or URL



-- 
Sylvain Letuffe liste at letuffe.org
qui suis-je : http://slyserv.dyndns.org