[OSM-talk] Mapnik tileset coherency issues

[Andrew MacKinnon]

On 10/18/07, Tom Hughes <tom at compton.nu> wrote:
> > I'm not convinced by the need for a queue for the high zoom tiles - I
> > think we should either render straight away or not at all. I think the
> > probability of any individual high level tile being re-visited is quite low.
>
> Umm.... Without the queue lots of people would just get blank space
> on the map. At peak times there is no way we can render all the needed
> tiles on demand and if they're not queued then they will still not be
> there the next time somebody looks at that area.

http://labs.metacarta.com/osm/, an alternative OSM slippy map, seems
to be able to render tiles in real time with quite acceptable
performance. It works from the latest database dump, and it caches
rendered tiles. I assume that OSM doesn't have enough CPU power to do
something like this itself, but this is what we should be aiming for -
perhaps rendering tiles in real time at off-peak times, and putting
them into a queue at peak times.