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Snapshots are based on Copy On Write (COW) technology. It is a way to save the original when changes occur to the data. Therefore, in the early days, not long after the snapshot was created, the capacity of the snapshot is small because there are not many changes. However, as time passes, the number of data changes gradually increases, and assuming that all areas of data are changed, snapshot space is required to store the entire original data might be required. In conclusion, we can say that the maximum capacity required for a snapshot is equal to the capacity of a full backup of your data.
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