It is an established industry observation that the data loses its value as it gets older. A fair estimate reveals that in a typical environment, the active data constitutes only 2-4%, aging data is close to 10% and the rest is rarely used. So it is cruel to treat all the data the same in terms of its storage. Same is true for SharePoint where the active BLOB content is only a small chunk of the total content that it carries.
Moreover, everyone is in agreement that there is visible cost saving associated with simply offloading BLOBs from transactional SQL Server storage to less-expensive external storage. However, externalization of BLOBs is only one important aspect of BLOB storage management. How you manage the physical storage of externalized BLOBs is the other one. Keeping all the active and aged BLOBs on one, expensive storage is not a wise idea. If you keep all those type of BLOBs, whether active or worn, in your primary storage tier of external storage, there is a fair chance you will get only a marginal benefit out of externalization, as the cost of storage at your primary, high-end tier shall keep on increasing. So, even after offloading 90-95% of data to external storage, you still manage to get only marginal cost savings, rethink of your storage strategy is in order.
A worthwhile approach for the storage of externalized BLOBs is structure the external storage as a hierarchy of multiple tiers with one storage tier corresponding to one age-based category of BLOBs. This hierarchical multi tiered storage needs to be structured in such a way that the most active BLOBs should reside at Tier-1 which is a high-end, faster-access storage. Similarly, the aging data should be kept at Tier-2 which is typically a SAN/NAS based storage and the archived/seldom-accessed data at Tier-3 which can typically be a Cloud. So based on this strategy, you effectively push lesser active content to the cheaper tiers.
StorageEdge has been built keeping this very important BLOB storage strategy in perspective. It provides “Multi-tiered Storage” that allows you to keep your active content in the most expensive storage and archives older content out to less expensive storage. This effectively ensures that the primary storage is not over-burdened with millions of documents.
StorageEdge manages the storage of externalized BLOBs on multi storage tiers through archiving based on two criteria:
1. Age: You can specify content age that allows your content to stay in a tier before it gets migrated to the next tier. This age can be specified separately for each storage tier and you can have as many tiers as you want.
2. Versioning: The other criterion is based on document versioning. Usually, everybody works on the latest copy of the documents so it is practical to archive the older versions to the cheaper storage tier
For Cloud Storage, you may want to control bandwidth, for which StorageEdge provides throttling.
So having multi-tiered storage not only reduces storage costs, but it also improves SharePoint performance because the most active storage no longer contains a huge amount of documents that can potentially inundate it.