RELSPACE

Read syntax diagramSkip visual syntax diagram RELSPACE vdev

Authorization

Privilege Class: G

Purpose

Use RELSPACE to return all extents on a device to its associated Extent Space Efficient pool. A user can release the space of any virtual device to which they have write access. This could be a dedicated DASD or a minidisk on a volume attached to the system.

Operands

vdev
is the virtual device number of the device to have backing tracks released.

Usage Notes

  1. The RELSPACE command is intended for the release of extents on Extent Space Efficient (ESE) DASD volumes. RELSPACE can be used to return extents to the device's associated ESE pool to be used for expanded usage by other devices.
  2. There is no guarantee that all data associated with the released tracks will be erased. If erasure is necessary, a policy such as using the CPFMTXA ERASE function before RELSPACE should be employed.
  3. The Query DASD SPACE-EFFICIENT command can be used to check the ESE pool utilization for a given device and its associated pool.
  4. Query DASD SPACE-EFFICIENT output will not correlate directly with the release of space of non-fullpack minidisks, when comparing the Query output before and after a release. The Release Allocated Space hardware function, invoked by the RELSPACE command, only releases FULL extents which begin and end on an integral hardware Extent boundary (for example, 21 cylinders). Since a non-fullpack minidisk can start and end on any real cylinder boundary, there may be partial hardware extents at the front and end of the minidisk which will not be released. Minidisks have to be defined to start and end on the real hardware Extent boundaries to circumvent this hardware restriction.
  5. RELSPACE to non-fullpack minidisks, including real cylinder 1-to-end minidisks, will fail with I/O errors if issued to Extent Space Efficient volumes with only Phase 1 (Full Volume) Release Allocated Space hardware support. Phase 2 (Partial Volume Extent) or higher Release Allocated Space hardware support is required.

Messages

  • HCP002E Invalid operand - operand
  • HCP003E Invalid option - {option command contains extra option(s) starting with option}
  • HCP006E Invalid device type - rdev
  • HCP022E A virtual device number was not specified or it is invalid.
  • HCP026E Operand was missing or invalid
  • HCP040E Device {rdev|vdev|ldev} does not exist
  • HCP263E Too many operands were supplied for this command.
  • HCP6432I vdev is not on an Extent Space Efficient Volume and is not valid for the RELSPACE command.
  • HCP6432I vdev is a PAV or HyperPAV alias device and is not valid for the RELSPACE command.
  • HCP6432I vdev does not have write access and is not valid for the RELSPACE command.