bgp tools for route optmization based on(performance, cost and reliability

Hi all, Looking for tools to optimize bgp routes based on performance, cost and reliability. Paid, open source, doesn't matter. Even presentations or research papers on performing tasks are welcome. But not configuration guides on multihoming :) Specifically in the context of a hosting provider who's multihomed to several tier 1's. What tools do you use for such optimization and just every day maintenance? Eric