A nodata Storage Checkpoint does not contain actual file data. Instead, this type of Storage Checkpoint contains a collection of markers indicating the location of all the changed blocks since the Storage Checkpoint was created.

See Types of Storage Checkpoints.

You can use either the synchronous or asynchronous method to convert a data Storage Checkpoint to a nodata Storage Checkpoint; the asynchronous method is the default method. In a synchronous conversion, fsckptadm waits for all files to undergo the conversion process to "nodata" status before completing the operation. In an asynchronous conversion, fsckptadm returns immediately and marks the Storage Checkpoint as a nodata Storage Checkpoint even though the Storage Checkpoint's data blocks are not immediately returned to the pool of free blocks in the file system. The Storage Checkpoint deallocates all of its file data blocks in the background and eventually returns them to the pool of free blocks in the file system.

If all of the older Storage Checkpoints in a file system are nodata Storage Checkpoints, use the synchronous method to convert a data Storage Checkpoint to a nodata Storage Checkpoint. If an older data Storage Checkpoint exists in the file system, use the asynchronous method to mark the Storage Checkpoint you want to convert for a delayed conversion. In this case, the actual conversion will continue to be delayed until the Storage Checkpoint becomes the oldest Storage Checkpoint in the file system, or all of the older Storage Checkpoints have been converted to nodata Storage Checkpoints.