Space reclamation
The following storage space reclamation techniques help to maintain a robust, efficient, and well performing data store:
Manage data reference at data container level which allows for the potential of reclaiming a whole container when the reference to the container drops to 0.
Maintain statistics on how much space may be reclaimed from a container to trigger compaction operation at the right time on a set of containers for segment level space reclamation.
Reference count increments are done before a backup job is completed to ensure backup image data is correctly protected.
Reference count decrements from image expirations are batch processed for efficiency.