Pool capacity

Calculate pool capacity using the following formula:

The capacity of the pool (MB) = Total number of pages * 42 - 4200.

4200 in the formula is the management area size of the pool-VOL with System Area.

Total Number of pages = Σ(floor(floor(pool-VOL number of blocks ÷ 512) ÷ 168)) for each pool-VOL.

floor( ): Truncates the value calculated from the formula in parentheses after the decimal point.

• VSP G800 or VSP F800: the total capacity of all pools is 6.5 PB if shared memory is installed.
• VSP G400, G600 or VSP F400, F600: the total capacity of all pools is 6.5 PB if shared memory is installed.
• VSP G200: the total capacity of all pools is 3.5 PB if shared memory is installed.

Max number of pool-VOLs

From 1 to 1,024 volumes (per pool).

A volume can be registered as a pool-VOL to one pool only.

Maximum number of pools

• VSP G800 or VSP F800: Up to a total of 128 pools per storage system. Pool numbers (0 to 127) are assigned as pool identifiers.
• VSP G400, G600 or VSP F400, F600: Up to a total of 64 pools per storage system. Pool numbers (0 to 63) are assigned as pool identifiers.
• VSP G200 : Up to a total of 64 pools per storage system. Pool numbers (0 to 63) are assigned as pool identifiers.

The maximum number of pools includes following pool types:

• Dynamic Provisioning (including Dynamic Tiering and active flash)
• Thin Image

Increasing capacity

You can increase pool capacity dynamically. Best practice is to add pool-VOLs to increase capacity by one or more parity groups.

Reducing capacity

You can reduce pool capacity by removing pool-VOLs.

Deleting

You can delete pools that are not associated with any DP-VOLs or with any Thin Image pairs or Thin Image snapshot data.

Subscription limit

From 0 to 65534 (%).

If you do not specify a value, the subscription is set to unlimited.

Thresholds

• Warning Threshold: You can set the value between 1% and 100%, in 1% increments. The default is 70%.
• Depletion Threshold: You can set the value between the warning threshold and 100%, in 1% increments. The default is 80%.
• Thresholds cannot be defined for a pool with data direct mapping enabled.

Data allocation unit

42 MB

The 42-MB page corresponds to a 42-MB continuous area of the DP-VOL. Pages are allocated for the pool only when data has been written to the area of the DP-VOL.

Tier

(Dynamic Tiering and active flash)

Defined based on the media type (see Drive type for a Dynamic Tiering and active flash tier, below). Maximum 3 tiers.

Maximum capacity of each tier

(Dynamic Tiering and active flash)

• VSP G800 or VSP F800: 4.0 PB (Total capacity of the tiers must be within 4.0 PB and the shared memory must be installed).
• VSP G400, G600 or VSP F400, F600: 4.0 PB (Total capacity of the tiers must be within 4.0 PB and the shared memory must be installed).
• VSP G200: 3.5 PB (Total capacity of the tiers must be within 3.5 PB and the shared memory must be installed).