Rendering a full planet isn't bad, I did up to zoom level 15 in 48 hours. 16 would take probably 48 hours by itself, and 17 would push into another week is my

Rendering a full planet isn't bad, I did up to zoom level 15 in 48 hours. 16 would take probably 48 hours by itself, and 17 would push into another week is my guess. But, mapnik2 is fast enough to render those tiles on the fly without a huge performance hit, about 1 second per metatile (enough to cover a couple small map pans on my big monitor). I am running it on 16gb of ram and a raid10 with 6 2tb drives. My next upgrade will be going full SSD and 196gb of ram, but that will also be a nominatim and pgrouting install, so the ram and SSD's are very important for importing the DB and indexing it inside of 1 month :) Just a tileserver isn't too bad at all.