[OSM-talk] Mapnik maxing CPU with Corine data set

[Frederik Ramm]

Hi,

Dermot McNally wrote:
> And here I begin to have a doubt - the sea polygons are tagged
> natural=water_sea. My assumption was that these would be ignored in
> rendering because no such tag is understood. But as it's a "natural"
> tag, won't it actually be considered a polygon and stored in the DB
> anyway? If so, it must be the culprit. What do you think?

It will certainly be stored in the DB because osm2pgsql does not know 
about rendering rules. Plus, there it at least one query in the standard 
rendering rules that will actually *retrieve* such a polygon and return 
it to the Mapnik library for processing (where it will then be discarded):

<Layer name="text-poly" status="on" srs="&osm2pgsql_projection;">
     <StyleName>text</StyleName>
     <Datasource>
       <Parameter name="table">
       (select 
way,aeroway,shop,access,amenity,leisure,landuse,man_made,"natural",place,tourism,NULL 
as ele,name,ref,military,waterway,historic,'no'::text as point
        from &prefix;_polygon
        where amenity is not null
[...]
           or "natural" is not null
[...]
       ) as text
       </Parameter>
       &datasource-settings;
     </Datasource>
</Layer>

You could try commenting that layer out to see if that improves the 
situation.

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00'09" E008°23'33"