PostgreSQL 11 Administration Cookbook

How to do it…

If your database is larger than 32 MB, then you'll probably benefit from increasing shared_buffers. You can increase this to a much larger value, but remember that running out of memory induces many problems.

For instance, PostgreSQL is able to store information on disk when the available memory is too small, and it employs sophisticated algorithms to treat each case differently and to place each piece of data on the disk or in memory, depending on each use case.

On the other hand, overstating the amount of available memory confuses such abilities and results in suboptimal behavior. For instance, if the memory is swapped to disk, then PostgreSQL will inefficiently treat all data as if it were the RAM. Another unfortunate circumstance ...