HP XP Racks - Manual (Page 74)

Smart Tiers
About tiered storage
In a tiered storage environment, storage tiers can be configured to accommodate different categories
of data. A tier is a group of storage media (pool volumes) in a THP pool. Tiers are determined by
a single storage media type. A storage tier can be one type of data drive, including SSD, SAS,
or external volumes. Media of high-speed performance make up the upper tiers. Media of low-speed
response become the lower tiers. Up to a maximum of three tiers can coexist in each Smart Tiers
pool.
Categories of data may be based on levels of protection needed, performance requirements,
frequency of use, and other considerations. Using different types of storage tiers helps reduce
storage costs and improve performance.
Because assigning data to particular media may be an ongoing and complex activity, Smart Tiers
software automatically manages the process based on user-defined policies.
As an example of the additional implementation of tiered storage, tier 1 data (such as mission-critical
or recently accessed data) might be stored on expensive and high-quality media such as
double-parity RAIDs (redundant arrays of independent disks). Tier 2 data (such as financial or
seldom-used data) might be stored on less expensive storage media.
Tier monitoring and data relocation
Smart Tiers uses tiers to manage data storage. It classifies the specified drives in the pool into tiers
(storage hierarchy). Up to three tiers can be defined in a pool depending on the processing capacity
of the data drives. Tiering allocates more frequently accessed data to the upper tier and less
frequently accessed data, stored for a long period of time, to the lower tier.
Smart Pool
With Smart Tiers, you can enable the Smart Pool option for an existing pool. The default is to allow
tier relocation for each THP V-VOL. Only the THP V-VOLs for which tier relocation is enabled are
subject to calculation of the tier range value, and tier relocation will be performed on them. If tier
relocation is disabled for all THP V-VOLs in a pool, tier relocation is not performed.
Figure 5 Relationship between Smart Pool and tier relocation
Tier monitoring and relocation cycles
Performance monitoring and tier relocation can be set to execute in one of two execution modes:
Auto and Manual. You can set up execution modes, or switch between modes by using either
Remote Web Console or RAID Manager.
74 Configuring thin provisioning