The pg_filespace table contains information about the filespaces created in a Greenplum Database system. Every system contains a default filespace, pg_system, which is a collection of all the data directory locations created at system initialization time.

A tablespace requires a file system location to store its database files. In Greenplum Database, the master and each segment (primary and mirror) needs its own distinct storage location. This collection of file system locations for all components in a Greenplum system is referred to as a filespace.