[OSM-dev] Tiling the Planet and Missing Nodes

[Stefan de Konink]

Hi Ben,

Ben Supnik wrote:
> I wrote (yet another) small C program to split the planet XML into 
> "tiles".  The only thing that I think is interesting about my tiler (vs. 
> the exisging ones) is that it can run the whole planet on a 32-bit machine.*

How do you handle the LargeFile allocation? Because I tried mmaping on 
some obscure 32 userspace valgrind 64 kerner lately, and that was prone 
to failure.

> But...it appears that there are cases where a node has been deleted from 
> the database while being referenced by a way.

Welcome in the fantastic world of OSM :D I thought had fixed all those 
instances two days ago :) Cool you found another one.

>  From my last run, way id 4043882 references node 365476284 that is not 
> present in the dump.  This is with planet version 090325.  Grep reveals 
> that 365476284 is only present in an "nd" tag as part of the ref= 
> statement. :-(
> 
> My question is: what is the right interpretation of a missing node? 
> Should I simply pretend the node reference does not exist (e.g. delete 
> the vertex from the way)?

The idea with that situation is for ways:
- Download the way; and just reupload it, then it will be solved in the 
next run (because the way download hides invisible nodes)

For relations:
- Download the relation; remove all nodes/ways/relations that you know 
that don't exist. Reupload it; will you get a 200; job well done ;)



Stefan