[Tilesathome] Improvements all over the place

[spaetz]

1) First and foremost: Florian Lohoff was annoyed enough by the API performance to program a new Read-Only-Map-Api (which could therefore only be names ROMA). Italians seemed to like the name :-). It can even fetch slices from ROMA, so perhaps we should switch to Pizza names rather than city names for the client.
He has one instance up and running on his machine so thanks go to him. It seems to hold up well (it's a fallback when the API doesn't reply. currently), and is being fed with osmosis minute diffs, so it should be only 5 minutes behind the real API.

There are independent other efforts going on to write t at h data APIs but he was quickest and offered a full testserver. I am excited to see what the other efforts will bring. We are flexible and are going to use whatever serves us best.

1b) the introduction of mirrored read-only APIs opens a whole lot of future possibilities. Imagine a few ROMAns sharing the load. Or specialized ROMAns that only keep data for one continent (and are quick at replying to requests for that). etc. exciting times.

2) The server locks entries that it is about to hand out to clients in the database now. WHile I had difficulties getting this to work, it does now. So you shouldn't see the same tileset be assigned to multiple clients. This was also a waster of client CPU and API bandwidth, so this would also contribute to increased performance.

You'll benefit from ROMA in the latest incarnation of stable and unstable clients.

spaetz