I care deeply about the environment, certainly more than I care personally about money, so it pains me to say that in most cases, making storage decisions based on power expenditure alone is not rational behavior. The world is driven by economics, and the stark reality is that the cost of power is only a drop in the bucket compared to the amount organizations spend on acquiring and managing their enterprise storage systems. Maybe someday a consumption tax or cap and trade system will tip the balance towards more responsible consumption of non-renewable resources, but in the meantime, the pricing of power (especially in the US) doesn’t give much economic incentive for good behavior. In fact, according to a report Forrester published recently, the amount of money typically spent on electricity to power and cool a TB of storage is only about 1% of the cost of buying that TB of storage (or about 4% of the annualized cost of buying that storage given that you only have to buy the TB once every 3-5 years but you power it every year). So, unfortunately for the environment, power cost itself doesn’t provide a very strong incentive for storage efficiency.
Fortunately though, the things that enterprises can do to reduce their power consumption costs are often the exact same things they can do to reduce the capital and operating expenses of their overall storage environment. Focusing on improving utilization (measured as the quantity of data written divided by the quantity of storage on hand) and increased usage of dense drives are the most straightforward and effective ways to reduce hardware acquisition costs as well as power consumption. There are many ways to achieve these objectives such as thin provisioning, reporting and reclamation to improve utilization, and tiering or wide striping to enable more use of dense drives. Whatever the motivation — economic, altruistic, or a combination of both — organizations that put significant focus on their utilization and dense drive ratios are likely to spend less money and be greener at the same time. And that’s good for everybody.
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