Internal storage pools

Internal GPFS storage pools are controlled by GPFS policies and commands. There are two types of internal GPFS storage pools, the required system storage pool and up to seven optional user storage pools. The system storage pool contains metadata for each file and may also contain user data. User storage pools can only contain user data.

The internal GPFS storage pool to which a disk belongs is specified as an attribute of the disk in the GPFS cluster. You specify the disk attributes as a field in each disk descriptor when you create the file system or when adding disks to an existing file system. GPFS allows a maximum of eight internal storage pools per file system. One of these storage pools is the required system storage pool. The other seven internal storage pools are optional user storage pools.

GPFS assigns file data to internal storage pools under these circumstances:
  • When the file is initially created; the storage pool is determined by the file placement policy that is in effect when at the time of file creation.
  • When the attributes of the file, such as file size or access time, match the rules of a policy that directs GPFS to migrate the data to a different storage pool.