Volume autosize allows a flexible volume to automatically grow or shrink in size within an aggregate. Autogrow is useful when a volume is about to run out of available space, but there is space available in the containing aggregate for the volume to grow. Autoshrink is useful in combination with autogrow. It can return unused blocks to the aggregate when the amount of data in a volume drops below a user configurable shrink threshold. Autoshrink can be enabled via the grow_shrink subcommand. Autoshrink without autogrow is not supported. The autogrow feature works together with snapautodelete to automatically reclaim space when a volume is about to get full. The volume option try_first controls the order in which these two reclaim policies are used.
By default autosize is disabled. The minimum autosize is set to the volume size, the maximum autosize is set to 120% of the volume size, and the autosize increment is set to the lesser value of either 1GB or 5% of the volume size at the time of command. The grow (or on) subcommand can be used to enable autogrow on a volume. The grow_shrink subcommand enables both autogrow and autoshrink. The reset subcommand resets the settings of volume autosize to defaults. The off subcommand can be used to disable autosize.
The -m switch allows the user to specify the maximum size to which a flexible volume will be allowed to grow. When increasing the size of a volume, Data ONTAP uses the increment size specified with the -i switch as a guide; the actual size increase may be larger or smaller. You can specify the increment amount either as a fixed size (in bytes) or as a percentage. The percentage is converted to a fixed size that is based on the current volume size. If the value of the -m parameter is invalidated by a manual volume resize or is invalid when autosize is enabled, the maximum size is reset to 120% of the volume size, and the autosize increment is reset to the lesser value of either 1GB or 5% of the volume size.
The -minimum-size switch allows you to specify the minimum size below which a flexible volume is not allowed to shrink. The default value is the size of the volume at the time grow_shrink is enabled. If the value of the -minimum-size parameter is invalidated by a manual volume resize or is invalid when autosize is enabled, the minimum size is reset to the volume size. The -shrink-threshold-percent switch allows you to specify the threshold percentage of used space below which the autoshrink action is triggered. Similarly, if the used space in a volume exceeds the value specified with the -grow-threshold-percent switch, the autogrow action is triggered.'