14 DAY TRIAL // Microsoft is hard at work on a new hard disk off-loading technique designed to save energy. While the first inherent conclusion that comes synonymous with the concept of energy saving is that this is nothing more than a green project from the Redmond company, the fact of the matter is that whatever the ecological impact, it is but a collateral benefit. Microsoft is of course hammering away at a new modality to cut down the total cost of ownership associated with its products. DiskEnergy is a Microsoft Research project designed to come up with a modality of saving power in data centers. The company has even published a white paper on the subject, titled: "Write Off-Loading: Practical Power Management for Enterprise Storage," and authored by Dushyanth Narayanan, Austin Donnelly, and Antony Rowstron, all with Microsoft Research.
"Power consumption is a major problem for data centers of all sizes which impacts the density of servers and the total cost of ownership. This is causing changes in data center configuration and management. Some components already support some power management features, for example server CPUs support dynamic clock and voltage scaling that enables power requirements to be reduced significantly during idle periods. Storage subsystems do not have power management and are consume a significant amount of power in the data center. Modern enterprise grade disks require approximately 10W when idle. As storage requirements generally increase in data centers, the number of disks in data centers is increasing proportionally," Microsoft revealed.
The Redmond company essentially looked into its own backyard, so to speak, namely it analyzed core servers in our data center for an entire week. The Write Off-Loading technique comes to supplement the simple modality of spinning down disks in order to reduce power consumption, while at the same time not contributing to reduce performance, capacity or effectiveness. The method is valid and will work on a wide variety of products including file servers, web servers, web caches, etc. At this point in time, Microsoft has failed to illustrate how will the future versions of its Windows server operating system incorporate the technique in order to minimize power consumption, but the results are bound to deliver a healthy impact on reducing TCO.
"Write Off-Loading is designed to save energy in enterprise storage. It allows blocks written to one volume to be temporarily redirected to persistent storage elsewhere in an enterprise data center. This alters the I/O access pattern to the volume, generating significant idle periods during which the volume's disks can be spun down, thereby saving energy. The evaluation confirms the analysis results: just spinning disks down when idle reduces their energy consumption by 28-36%, and write off-loading increases the savings to 45-60%. We believe that write off-loading is a viable technique for saving energy in enterprise storage," Microsoft added.