Saturday, June 19, 2010

Comparing Performance Tiering to Archival Tiered Solutions

Tiered storage is a technology that enables the storage administrator to match the value and requirements of the data with the performance and cost of the storage. However not all tiering solutions deliver the same value proposition, despite the marketing buzz.

Storage tiering has evolved over the past 12 to 18 months into what can be called performance tiering and archival tiering.

Performance tiering is where the data placement decision is performance driven and focus on optimizing the use of tier 0 and tier 1 storage to optimize application performance . It is a technology that can fully integrate and exploit the advantages of solid state disk.

Archival tiering is the more traditional and pragmatic view of storage tiering, think HSM. It’s focus is to free-up expensive Tier 1 storage, optimizing the usage of storage assets by simply demoting aged and inactive data to lower and less expensive tiers of storage with the lowest tier being tape offload.

What separates performance tiering from the more lethargic traditional implementations is granularity and responsiveness. Performance tiering continuously monitors data access profiles at a small block size (4k to 64K) and responds near instantly to changes in workload data access patterns. This requires performance tiering solutions to be highly automated and in at least one implementation reach the level best described as autonomic.

In comparison, traditional approaches look at much larger data chunks, or even at the file level, and use a batch approach to move data between tiers in time intervals to be determined by the administrator. In short there is a delay in the detection of data access profile changes and the movement of the data to a more appropriate storage. Ok for traditional tiering applications but not for performance tiering.

The primary objective of performance tiering is to deliver greater performance and eliminate storage IO bottlenecks whereas the primary objective of traditional tiering solutions is to more effectively manage storage assets. There are many solutions currently available but beware of tradition solutions that have been repurposed to include SSD technology but do not have the characteristics that can truly manage and exploit the significant performance gains that solid state brings to the storage hierarchy.

4 comments:

Joshua Smith said...
This comment has been removed by a blog administrator.
Joshua Smith said...
This comment has been removed by a blog administrator.
Joshua Smith said...
This comment has been removed by a blog administrator.
Joshua Smith said...
This comment has been removed by a blog administrator.