[OSM-dev] rendered

[Andy Allan]

On Tue, Aug 4, 2009 at 2:44 AM, John Smith<delta_foxtrot at yahoo.com> wrote:
>
> --- On Mon, 3/8/09, Jon Burgess <jburgess777 at googlemail.com> wrote:
>
>> - The data source needing page lots of data into RAM
>> needing lots of
>> disk IO (e.g. large postgres DB or shapefiles)
>
> There is 2G of system ram, although that is shared between various things running obviously.
>
>> - With the postgis data source: setting estimated_extent to
>> false and
>> not providing a fixed extent for the layer. This causes
>> Mapnik to issue
>> an extent() query to the DB which normally results in it
>> parsing all the
>> data to determine the extent.
>
> Ok, how do I set an extent or find out if it is set or ... ?

Check your Layer definitions for something along the lines of

    <Parameter name="estimate_extent">false</Parameter>
    <Parameter name="extent">-20037508,-19929239,20037508,19929239</Parameter>

If you have estimate_extent set to true it'll only cover about the
95th percentile of the data - so misses off southern south america and
africa in my experience. So you need to set it to false, and specify
an extent *in the correct projection*. If your layers already have
this then this isn't the problem.

Cheers,
Andy