When in doubt about how to tune a PostgreSQL server, try PGTune. This project will read your current postgresql.conf and output a new one with tuning settings designed for the machine it's running on. As an important side note, this will not take into account the necessary memory for the message queue or the web server, so leaving a small amount of extra resources by slightly tuning down these settings can help with performance.
Please note that PGTune assumes the only purpose of the node it is running on is to serve a Postgres server. These settings will be difficult to use on a single monolithic master, and tkishel/pe_tune will be a much more useful tool for configuring these servers.
We'll want to begin ...
