Well this post should be quite simple to write. Lets start with the problem. Does your open street map server suffer from extremely slow tile rendering? The solution is quite simple and best of all it’s FREE!
Okay enough with the sales pitch. If your open street maps tile server has slow tile serving ever with good hardware specs. Lots of MT, SSD, and RAM. Make sure that if you are using the Open Street Maps carto rendering package to run scripts/indexes.py this file will create an copyable list of PostgreSQL statement to generate indices necessary to speed up the process of rendering tiles.
These indicies have increased my tile rendering speeds from 5 tiles/s to 1k tiles/s+