Pools

A storage pool is a collection of storage that identifies a set of storage resources. These resources provide the capacity and management requirements for arrays and volumes that have the same storage type, either fixed block (FB) or count key data (CKD).

Pool pair
The DS8000® Storage Management GUI includes a preconfigured tool that automatically sets up a pool pair when you create pools. Pools are required to be created in pairs to balance the storage workload. Each pool in the pool pair is controlled by a separate processor node (either Node 0 or Node 1). Balancing the workload helps to prevent one processor from doing most of the work and results in more efficient workload balancing, which can improve overall system performance.

Pool properties

You can view the properties of a pool in the Arrays by Pool table, the Volumes by Pool table, or the Pool Properties window.

Storage type
The type of storage architecture, either CKD for IBM® Z hosts or FB for open systems hosts, for which a pool is provisioned.
Name
The user-defined name or identification of the pool.
Node
The processor node (0 or 1) that manages all I/O for the array.
Capacity
The capacity bar displays the following parameters:
  • Total capacity for the pool
  • Allocated capacity
  • Available capacity
  • Safeguarded copy volume capacity
  • System metadata capacity
  • Over-provisioned ratio
    Note: The over-provisioned ratio is the ratio of the provisioned capacity to the total capacity allowed for volumes. The total capacity that is allowed consists of both the allocated and available capacity for all volumes.
  • Drive classes, including the capacity, speed, and type of the drives in the pool
TSE repository
The track space efficient (TSE) repository contains allocated physical storage (also known as the provisioned capacity) for TSE storage of FlashCopy® volumes. A TSE repository allocates physical storage space only during a write transaction, on an as-needed basis.
ESE repository
The extent space efficient (ESE) repository contains provisioned capacity that is allocated for each extent as needed.
Encryption
The encryption state of all data in the pool. Encryption protects data from unauthorized access and helps to keep your data secure.
Easy Tier®
The state of Easy Tier processing in the pool:
Managed
The pool is managed by Easy Tier.
Disabled
The pool is not managed by Easy Tier.
Monitor Only
Easy Tier is monitoring the pool but will not migrate data.
Learning Paused
The process of learning about volumes in the pool is paused.
Migration Paused
Easy Tier migrations of the pool are paused.
Arrays
The number of arrays that are assigned to the pool.
Volumes
The number of volumes that are associated with the pool.
Extents
The number of extents that are associated with the pool. An extent is a unit of data that is used to manage the mapping and allocation of data between drives and volumes.