Formatted Pool Capacity; Used Capacity, Mapped Capacity, And Reserved Capacity; Rebalancing The Usage Level Among Parity Groups - HP XP7 User Manual

Tier of deleted pool-VOLs
Tier 2

Formatted pool capacity

The formatted pool capacity equals the capacity of the initialized free space and the reserved
capacity of a pool, but not the capacity of all free space and reserved capacity of the pool. The
free space of the pool is monitored by a storage system. Space is formatted automatically if needed.
You can confirm the formatted pool capacity in the View Pool Management Status window (see
"View Pool Management Status window" (page
the format speed of free space and reserved capacity of the pool is adjusted.
New pages are allocated, then initialized, during data write operations to the V-VOL. If a significant
number of new pages are allocated, initialization might be delayed as a result of conflicts between
data write and new page initialization processes. You can initialize the free space of a pool in
advance to prevent delays in data write operations.
If you want to change the method of performing the function to format the free space of a pool,
contact HP technical support.

Used capacity, mapped capacity, and reserved capacity

The used capacity is the total capacity of pages that are assigned and reserved for each V-VOL.
The mapped capacity is the total of pages which contain user data and control information of each
V-VOL. The reserved capacity is the total of pages reserved in each V-VOL for which the full
allocation function is enabled.

Rebalancing the usage level among parity groups

If multiple parity groups that contain LDEVs used as pool-VOLs exist, rebalancing can improve
biased usage rates in parity groups. Rebalancing is performed as if each parity group were a
single pool-VOL. After rebalancing, the usage rates of LDEVs in a parity group may not be balanced,
but the usage rate in the entire pool is balanced.
104 Configuring thin provisioning
Order in which pages are
allocated to tiers
Tier 2 and Tier 1
315)). Dependent on the load of the storage system,
Description
If there is no free space in Tier 1, pages are
allocated to Tier 2.
If there is free space in Tier 2, pages are
allocated to Tier 2.
If there is no free space in Tier 2, pages are
allocated to Tier 1.