PostgreSQL 10 High Performance - Third Edition

Memory

How much to prioritize memory for your application depends on the size of the working set of data needed to handle the most common operations. Generally, adding more RAM will provide a significant performance boost. There are a few situations where you'd be better served doing something else instead:

• If your data set is small enough to fit into a smaller amount of RAM, adding more won't help you much. You probably want faster processors instead.
• When running applications that scan tables much larger than what you can feasibly purchase as RAM, such as in many data warehouse situations, you might be better served by getting faster disks rather than more memory.

The normal situation where more memory helps most is when the data you ...