The storage pool

Every instance of the database server has a storage pool. The storage pool contains information about the directories, cooked files, and raw devices that the server can use if necessary to automatically expand an existing dbspace, temporary dbspace, sbspace, temporary sbspace, or blobspace.

When the storage space falls below a threshold defined in the SP_THRESHOLD configuration parameter, the database server can automatically run a task that expands the space, either by extending an existing chunk in the space or by adding a new chunk.

You can use SQL administration API commands to:

  • Add, delete, or modify an entry that describes one directory, cooked file, or raw device in the storage pool. The server can use the specified directory, cooked file, or raw device when necessary to automatically add space to an existing storage space.
  • Control how a storage pool entry is used by modifying two different dbspace sizes that are associated with expanding a storage space, the extend size and the create size.
  • Mark a chunk as extendable or not extendable.
  • Immediately expand the size of a space, when you do not want the database server to automatically expand the space.
  • Immediately extend the size of a chunk by a specified minimum amount.
  • Create a storage space or chunk from an entry in the storage pool
  • Return empty space from a dropped storage space or chunk to the storage pool

The storagepool table in sysadmin database contains information about all of the entries in a storage pool for a database server instance.