A nodata Storage Checkpoint only contains file system metadata—no file data blocks. As the original file system changes, the nodata Storage Checkpoint records the location of every changed block. Nodata Storage Checkpoints use minimal system resources and have little impact on the performance of the file system because the data itself does not have to be copied.
In Updates to a nodata clone, the first block originally containing A is updated. The original data is not copied to the storage checkpoint, but the changed block is marked in the Storage Checkpoint. The marker indicates which data has changed.
Updates to a nodata clone
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See Showing the difference between a data and a nodata Storage Checkpoint.