[OSM-dev] running a local server

[Andy Allan]

On 11/2/07, Keith Sharp <kms at passback.co.uk> wrote:
> On Fri, 2007-11-02 at 11:21 +0000, Andy Allan wrote:
> > If you're running a low-bandwidth, limited area map, it's 100 times
> > easier than this. Pre-render your tiles (or just copy them from the
> > main tileserver) and just put them in the correct hierarchy on your
> > webserver, e.g.
> >
> > http://example.com/12/2173/1398.png
> >
> > Openlayers will then make straightforward HTTP requests for the tiles,
> > and your webserver will simply reply with the file from the
> > filesystem. This is how it works for the cycle map - all the images
> > are prerendered on a machine at home, and then uploaded to a dumb
> > webhost that is nothing more than apache serving .png files.
>
> I have a few of questions about this approach:

Sure, Dave answered some of this in a different post.

> 1) Are you rendering just the UK?

Nope, I render the Netherlands, some other parts of Europe and parts
of the US too.

> 2) How long does the rendering take and what spec machine is doing the
> rendering?
> 3) How much disk space do the rendered tiles take up?

This week, only 9.5 hours on a modest athlon64 3400+ to render 518,000
tiles (3.4 Gb).

It takes only a couple of minutes (if that) to render a large town to
reasonably high zoom levels - mapnik is really, really fast at doing
this.

> 4) What are you using to drive Mapnik to do the rendering?  Does this
> automagically create the correct directory hierarchy?

A modified version of generate_tiles.py from
http://svn.openstreetmap.org/applications/rendering/mapnik/generate_tiles.py
- yep, it creates tiles in the right hierarchy.

Cheers,
Andy