[OSM-dev] amazon AMIs for a full blown openstreetmap.org-like server

[Stefan de Konink]

Op 08-01-10 15:09, jamesmikedupont at googlemail.com schreef:
> I dont know all the details of mapnik, but from what I have seen,
> using the postgres database is not needed in all cases.
> I am thinking about

It is not required to use the database, but the overhead is in the 
rendering. I do agree that PostgreSQL will not always give you the 
fastest results ;)

> Well you mean a 4k page in memory. But you dont need to have all that
> data memory mapped.
> It could be just 4k of data on disk in an array. It could also just be
> a tiny osm file that is parsed when needed.

Tiny would have to be an osmtile in binary format, agreed?

> Well again, I have not really gotten into mapnik. But I can.

Please do so :)

> But lets try and define the problem as rendering an osm file to a
> tile. That osm file is updated , and rerendered.
> All the data needed to render is just stored in osmxml in a nice
> sorted way. You never need all the data at once because you only
> render a tile at a time.

You don't want to store it in XML, it will get huge... and requires 
again the parsing overhead. And as I pointed out before, we prefer to 
render 64 tiles at a time.


> but you dont need a full postgres database functionality, you just
> have very basic update of pages of data.

In your idea, how would you *update* the storage?



Stefan