When snapshot data is stored, the data of the P-VOL at that point in time is stored as snapshot data. The following describes how snapshot data is stored. Storing snapshot data is also referred to as "splitting a pair".
In CCI, you store snapshot data using the raidcom modify snapshot -snapshot_data split. The location management information of the P-VOL (metadata) is copied to the S-VOL. After the copy processing finishes, the metadata for that data (in the P-VOL) is created in the S-VOL.
The location management information is a metadata that manages where the data of the P-VOL and S-VOL is located in the pool. Because only metadata is copied, snapshot data is stored in a short time.
After the snapshot data is stored, the status of the Thin Image Advanced pair is changed to PSUS (pair split).