Posted by: Randy Kerns
A recent conversation I had about the cost of storage made me think that talking about the cost of storage is the wrong way to approach it. The discussion should be about the value that storage delivers.
Trying to explain the complex nature of meeting specific demands for storing and retrieving information and advanced features for management and access is difficult when discussing it with someone who is focused only on how much it costs to store the information.
When storage costs, there is an implicit assumption that all factors are equal in storing and retrieving information. But several factors should take priority:
• How fast must the information be stored and retrieved? The ingestion rate (how fast data arrives) and how long it takes for the data to be protected on non-volatile media with the required number of copies has a big impact on applications and potential risk. Retrieving information is about how fast the data can be accessed (latency) and the amount of IOPS or continuous transfer (bandwidth) that can be sustained.
• What type of protection and integrity are required? Information has different value and the value changes over time. Information protection may be as simple as a single copy on non-volatile storage or as complex as multiple copies with geographical dispersion. Integrity is another concern. Protection from external forces so the loss of one or more bits of data can be detected and corrected is highly valuable and often assumed without understanding what is involved. Additional periodic integrity checking is another assurance for the information. It also answers the question posed for many in IT: “How do you know that is the same data that was written?”
• The longevity of the information can have a major influence on storing and retrieving. A significant percentage of information is kept more than 10 years. Compliance requirements dictate the length of time and manner of control of information in regulated industries. Storing information on devices that have limited lifespans (such as when you can no longer purchase a new device to retrieve information), means that other considerations must be made. If the information can be transparently and non-disruptively migrated to new technology without additional administrative effort or cost, that should be a factor in the selection process.
Here’s an example of how this works with a real IT operation that needed to increase its transactions per second. Increasing the number of transactions allowed the organization to get more done over a period of time, expand its business and provide better customer service. In this case, more capacity was not the issue – the capacity for the transaction processing was modest. After evaluating where the limitations were, it was clear that adding non-volatile solid state technology for the primary database met and even exceeded the demands for acceleration. Storage selection was not based on the cost as function of capacity ($/GB). It was based on the value returned in improving the transaction processing and gaining more value from the investments in applications and other infrastructure elements.
Storage must be evaluated on the value it brings in the usage model required. Comparing costs as a function of capacity can make for bad judgments or bad advice.
(Randy Kerns is Senior Strategist at Evaluator Group, an IT analyst firm).