DaveWentzel.com            All Things Data

Tiered Storage


"Tiered storage" is another term SAN guys throw around to make themselves sound important.  It's an easy concept.  We are designing storage for a particular application.  If you need lower seek times consider designing a storage tier that uses short stroking.  Also, a higher tier could have a better RAID level (10 vs 5) or a different block size (smaller for transactional dbs, larger for streaming applications). 
Other aspects...better tiers will have higher disk speeds, different caching, utilization, etc. 
It's common for most data centers to have three tiers of storage...however, the number of tiers is completely up to you.  Most folks agree that in a three tier model the tiers look something like:
  • Tier 1:  highest availability and highest performance. 
  • Tier 2:  generally considered 'nearline' storage
  • Tier 3:  tape or other 'archive' storage. 

SAN Home

Add new comment