You can achieve maximum space savings on FlexVol volumes by running data compression before creating Snapshot copies. After data compression is enabled, by default only the new data that is written to the disk is compressed. However, you can compress
the data that existed on the disk prior to enabling compression.
When existing data is compressed, by default the data containing shared blocks and data that is locked in a Snapshot copy is bypassed.
You should be aware of the following guidelines when using the data compression operation:
- For source FlexVol volumes with Snapshot copies that cannot be deleted (for example, volumes created by FlexClone, SnapMirror, LUN clone, and dump operations), you can compress existing data in default mode, in which data that is locked in Snapshot copies is bypassed.
- You can disable Snapshot copy creation temporarily until the data compression operation is complete.
- You should disable the deduplication schedule until the data compression operation is complete.
- For a volume that is the source for NDMP copy, dump, volume SnapMirror, qtree SnapMirror, or SnapVault relationships, you should run the data compression operation before the initial baseline is created.
- You should disable volume SnapMirror and SnapVault schedules until the data compression scanning is complete.
- If you create a FlexClone volume when decompression is active on the parent volume, then the decompression operation does not run on the cloned volume.