Hi Tim,
For analysing I take me: http://toolserver.org/~mazder/tirex-status/?short=0&extended=0&refre... and create some diagrams in OpenOffice Calc: http://toolserver.org/~kolossos/docs/tirex-stat02.xls
Thanks for those graphs!
There it is possible to see rendertime per layer, render time per zoomlevel and average-render- duration per metatile. So I would say that we have no problem in z0-z10 and z14-z18. In z11-z13 we have a explosion of render time. The half of render time comes from default style, the biggest part of the other half comes from the next 10 popular styles. The other 280 styles have in the moment nearly no incluence, but off-course we want locale-maps in higher zoomlevel in different Wikipedias what seems not possible with technic we have today. It's also detectable that special overlays like "lightning" rendering much faster than full styles (no wonder) and should be to prefer.
On a side note: bw-noicons needs double the time for rendering as osm-no-lables - shouldn't they be more-a-less equal in cpu-time?
[The following is only about 'full'-styles]
Looking at Zoom 12: http://www.openstreetmap.org/?lat=49.4592&lon=10.9644&zoom=12&la...
Do we really need a weekly update on that zoom? What you can see is: - main streets (secondary and up) and trains - forests and fields - names of villages and cities
IMHO those things don't change often enough to let them jam the queue. Rendering them once a month would be ok.
Secondly: Is it correct, that tiles never get deleted? So every tile gets rerendered according to the timetable, no matter if it was requested from a user during that period or not? So maybe a deletion strategy would be handy..
Regards, Thomas