Saving disk space by using file folding

What file folding means and how it saves disk space

File folding describes the process of checking the data in the most recent snapshot, and, if it is identical to the snapshot currently being created, just referencing the previous snapshot instead of taking up disk space writing the same data in the new snapshot. Disk space is saved by sharing unchanged file blocks between the active version of the file and the version of the file in the latest snapshot, if any.

The filer must compare block contents when folding a file, so there is a tradeoff between performance and space utilization.

If the folding process reaches a maximum limit on memory usage, it is suspended. When memory usage falls below the limit, the processes that were halted are restarted.

How to turn file folding on

To turn file folding on, complete the following step.

Step	Action
1	Enter the following command: options cifs.snapshot_file_folding.enable on

How to turn file folding off

To turn file folding off, complete the following step.

Step	Action
1	Enter the following command: options cifs.snapshot_file_folding.enable off This option is off by default.

Note
This option is not available to NFS users in this release.