Portal:Storage

Wikitip

Know the difference between utilization and allocation

• Allocation = How efficiently you use what you buy – allocated storage space vs. how much storage you bought. BUT if you over-allocate your storage, or do not allocate space efficiently, this rate can look good. This can be misleading if not measured the right way – you can overlook a significant amount of wasted space.

• Utilization = How frequently data is re-referenced (i.e. utilized). We have found that up to 40% of a primary disk array’s capacity holds data that is inert – data that has not been referenced in 6 months or more. Does anyone want t o spend tier 1, disk/SAN prices on data that is not referenced for over 6 months?

Some storage vendors use the terms incorrectly or interchangeably – so if a storage manufacturer says their arrays offer great utilization rates, make sure they are not just talking about allocation.

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