[OSM-dev] Alternative tile webserver needed?

[Lars Aronsson]

Stefan de Konink wrote:

> I'm sorry but I don't see the relation between complexity and 
> least cost routing. It is just a sign that people are 1) just 
> lucky they don't pay any bills 2) didn't think about scalablity.
> 
> Isn't it an interesting idea to have different servers for 
> different continents on the *same* location? I still *strongly* 
> believe that splitting the 'higher zoomlevels' to local servers 
> because they are more used locally. It saves a BUNCH of 
> diskspace per server and probably makes the operation less 
> complex per server.

To clarify, I only speak my own opinion here.  I'm just a mapper.

You can design a system split between two computers, still having 
them in the same room. Today OSM has a classic two-tier solution, 
using a "vertical" distribution of labour between one computer as 
web front-end and the other as database back-end.  But you can 
also do the split horizontally, serving the western hemisphere 
from one computer and the eastern hemisphere from the other 
computer.  Or 64 computers, each serving a slice of the world. The 
horizontal split makes the system more complex.  This can 
certainly be managed, but it's often easier and more economic to 
just buy a stronger, single server.

But then, you can compare any of these scenarios with distributing 
the servers to different physical locations.  That was what I 
thought you suggested and I protested against.  This ultimately 
requires the coordination of people taking care of the different 
installations, including synchronized holidays.  And when anything 
fails, they would start to blame each other instead of focusing on 
finding the problem in their own server. What would the benefit 
be?  Shorter ping times?  That's not our problem.  Lower Internet 
bills?  I don't think that's our problem either.  Is it?  The 
discussion was started because the tile server had a full disk.  
That's a problem that can be solved for 100 euro by just buying a 
new disk.  We're probably just waiting for the stores to open.

Any of these exercises can be fun and interesting in their own 
right, but *that* is not the purpose of the OSM project.


-- 
  Lars Aronsson (lars at aronsson.se)
  Aronsson Datateknik - http://aronsson.se