PgFincore and the OS Page Cache (Is my table in memory ?) While PostgreSQL can see the contents of shared buffers, it does not know about the OS page cache, which in turn tells which pages are actually in memory. PgFincore provides this information, which allows us to: Preload the exact pages that PostgreSQL will probably want in order to respond more quickly to the first queries on server restart. Try to improve planner choice and cost estimation. It suggest ideas to : Keep pg_dump from trashing the OS Page Cache Explicitly ask for a non-cached sequential scan. PgFincore also provides information about how the data in the OS page cache is distributed.