Many, if not most of these settings, show up frequently in the PostgreSQL mailing lists. As a result, we used many of the prescribed values or formulas. However, several of these settings show up very often; a tool is available to estimate them by analyzing the server hardware and by taking parameter hints. The pgtune program is a contributed utility for automatically estimating many system-dependent server settings.
We urge caution if you are relying primarily on this utility. It is extremely liberal when estimating work_mem and shared_buffers and doesn't seem to modify checkpoint_segments at all. Still, we feel that the values it produces are much better than the defaults for larger servers, so feel free to experiment.
