How you can determine and control a volume's space usage in the aggregate

You can determine which FlexVol volumes are using the most space in the aggregate and specifically which features within the volume. The volume show-footprint command provides information about a volume's footprint, or its space usage within the containing aggregate.

The volume show-footprint command shows details about the space usage of each volume in an aggregate, including offline volumes. This command bridges the gap between the output of the volume show-space and aggregate show-space commands. All percentages are calculated as a percent of aggregate size.

The following example shows the volume show-footprint command output for a volume called testvol:

cluster1::> volume show-footprint testvol

      Vserver : thevs
      Volume  : testvol

      Feature                                   Used    Used%
      --------------------------------    ----------    -----
      Volume Data Footprint                  120.6MB       4%
      Volume Guarantee                        1.88GB      71%
      Flexible Volume Metadata               11.38MB       0%
      Delayed Frees                           1.36MB       0%
      Total Footprint                         2.01GB      76%

The following table explains some of the key rows of the output of the volume show-footprint command and what you can do to try to decrease space usage by that feature:

Row/feature name Description/contents of row Some ways to decrease
Volume Data Footprint The total amount of space used in the containing aggregate by a volume's data in the active file system and the space used by the volume's Snapshot copies. This row does not include reserved space.
  • Deleting data from the volume.
  • Deleting Snapshot copies from the volume.
Volume Guarantee The amount of space reserved by the volume in the aggregate for future writes. The amount of space reserved depends on the guarantee type of the volume. Changing the type of guarantee for the volume to none.
Flexible Volume Metadata The total amount of space used in the aggregate by the volume's metadata files. No direct method to control.
Delayed Frees Blocks that ONTAP used for performance and cannot be immediately freed.

For SnapMirror destinations, this row has a value of 0 and is not displayed.

No direct method to control.
File Operation Metadata The total amount of space reserved for file operation metadata. No direct method to control.
Total Footprint The total amount of space that the volume uses in the aggregate. It is the sum of all of the rows. Any of the methods used to decrease space used by a volume.