[Tilesathome] t at h zapping happily along :-))

[spaetz]

Hi guys and girls. The blank tile reduction finished: we are down from 135mio entries to 7mio. The server is now dedicated again to processing tile uploads and, with the latest improvements done by OJW and me, it copes very well:

- MySQL requests are now being serverd mostly from cache, rather than searching the disk. The number of cache_hits seems to be around 50% of all requests.

- Before it oculd manage about 85 user requests (full tilesets)/hour. Now it does 250-300 without complaining too loudly. Mind that makes us upload, unzip and register  about 4-5 tilesets per minute with 1600 or 340 files each. (besides serving all these tiles).

- Server load is reasonable low: 1-2 while it is as busy as it can)

- Given the improvements and the fact that there seems to be a good deal of clients that take a request but never hand a result back, I re-request a tileset now after only 1h after it has been handed out to a client but got no result back. It is rerequested after another hour again and then in six hour intervals (I think another 4 times) before we give up. This has brought down the number of concurrent active requests from a constant 400 or so to (currently) a few dozen.

- Although there is still potential of optimizing and improving the processing and storing of uploads (and in improving the request queue and the priority scheme), I'd say we are in good shape currently. Of course, if we improve our service with more layers and other stuff, we'll have to see how we can scale/improve.

"...All was well."

spaetz
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