Storing data written to DP-VOLs
Data written by hosts to DP-VOLs is stored in pool volumes on a page basis. When pool volumes are created from a parity group with accelerated compression enabled, data is compressed and stored to drives.
The compression ratio of data varies for each data update or data deletion operation. The capacity that is displayed as the used capacity is the user data capacity that is compressed by accelerated compression. Therefore, for a pool containing pool volumes in accelerated compression-enabled parity groups, the smaller capacity of the following two capacities is displayed as the pool capacity to which data can be stored: either the total capacity of the pool volumes, or the capacity of the parity groups to which the pool volumes are defined. When a pool contains both pool volumes carved from accelerated compression-enabled parity groups and pool volumes carved from other parity groups, the total capacity of the pool capacity is calculated by the following formula:
Total-writable-capacity-of-the-pool = Capacity-that-can-store-data-in-the-accelerated-compression-enabled-pool + Total-capacity-of-pool-volumes-carved-from-other-parity-groups
The purchased license of Dynamic Provisioning is consumed with respect to the defined pool capacity.