[OSM-talk] Tile caching (osm startpage)

[Bernhard zwischenbrugger]

Hi all

I'm sitting in Phom Penh and have very slow internet.
The tiles come in very very slow.

I'm working on a new javascript map...
full story: http://www.mail-archive.com/dev@openstreetmap.org/msg10669.html

The internet is too slow here for developing, so I had to install a 
local image proxy.
Now it's fast as hell. It's faster than at home.

If a tile is changed I will see the old version for a long time.
But it's fast and usable.


----HTTP HEAD

Google Cache Time:
Cache-Control: public, max-age=22222222  //feels like one month (I 
didn't calculate)

OSM Cache Time:
eTag (no cache)

----- Story

In many countrys (like cambodia) the ping is very long. It can be easily 
some seconds.
osm.org is slow slow slow.
It takes long time until all the tile for the osm startpage are loaded.
But then the problem starts.
Every move I make on the map is soooo slow.
Even if I was looking at the same spot on the map a couple of days ago.


For visitors of osm.org a good caching is important.
For editors of osm.org it's important to have the newest version of the 
tiles.

For visitors (not logged in) there could be a diffent caching than for 
editors (logged in).

Caching is important if you sit somewhere in a developig country with 
slow internet connection.

----Implementation

Tileserver visiter
cache.openstreetmap.org

Tileserver editor
tiles.openstreetmap.org

The Servers should deliver headers for long and short caching time.
The map for logged in users should load images from
tiles.openstreetmap.org.
(extensible rules...)


Never mind, I was just thinking about that and want to distribute it.

Wish you a nice day

Bernhard







------OSM:

HEAD http://a.andy.sandbox.cloudmade.com/tiles/cycle/17/37480/50153.png
200 OK
Cache-Control: max-age=440434
Connection: close
Date: Fri, 05 Mar 2010 14:37:11 GMT
ETag: "d096ddafba32c0da609007e224530ccd"
Server: Apache/2.2.8 (Ubuntu)
Content-Length: 45409
Content-Type: image/png
Expires: Wed, 10 Mar 2010 16:57:46 GMT
Client-Date: Fri, 05 Mar 2010 14:37:11 GMT
Client-Peer: 75.101.147.222:80
Client-Response-Num: 1


-----GOOGLE:

HEAD "http://mt1.google.com/vt/lyrs=m@118&hl=de&x=3&y=6&z=4&s=Galileo"
200 OK
Cache-Control: public, max-age=22222222
Connection: close
Date: Fri, 05 Mar 2010 14:45:02 GMT
Server: maptiles-versatile
Content-Length: 19810
Content-Type: image/png
Client-Date: Fri, 05 Mar 2010 14:45:02 GMT
Client-Peer: 64.233.189.136:80
Client-Response-Num: 1
X-Content-Type-Options: nosniff
X-XSS-Protection: 0


Sorry, I posted something similar bevor:
http://www.mail-archive.com/talk@openstreetmap.org/msg23461.html


Bernhard