Veritas Storage Foundation 5.1 SP1: Storage and Availability Management for Oracle (5900-1504, April 2011)

Tiered storage is the assignment of different types of data to different storage
types to improve performance and reduce costs. With SmartTier, storage classes
are used to designate which disks make up a particular tier. There are two common
ways of defining storage classes:
■ Performance, or storage, cost class: The most-used class consists of fast,
expensive disks. When data is no longer needed on a regular basis, the data
can be moved to a different class that is made up of slower, less expensive
disks.
■ Resilience class: Each class consists of non-mirrored volumes, mirrored
volumes, and n-way mirrored volumes.
For example, a database is usually made up of data, an index, and logs. The
data could be set up with a three-way mirror because data is critical. The index
could be set up with a two-way mirror because the index is important, but can
be recreated. The redo and archive logs are not required on a daily basis but
are vital to database recovery and should also be mirrored.
SmartTier policies control initial file location and the circumstances under which
existing files are relocated. These policies cause the files to which they apply to
be created and extended on specific subsets of a file systems's volume set, known
as placement classes. The files are relocated to volumes in other placement classes
when they meet specified naming, timing, access rate, and storage capacity-related
conditions.
In addition to preset policies, you can manually move files to faster or slower
storage with SmartTier, when necessary. You can also run reports that list active
policies, display file activity, display volume usage, or show file statistics.
SmartTier building blocks
To use SmartTier, your storage must be managed using the following features:
■ VxFS multi-volume file system
■ VxVM volume set
■ Volume tags
■ SmartTier management at the file level
■ SmartTier management at the sub-file level
About VxFS multi-volume file systems
Multi-volume file systems are file systems that occupy two or more virtual volumes.
The collection of volumes is known as a volume set, and is made up of disks or
Understanding storage tiering with SmartTier
SmartTier building blocks
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