Greener Storage

Storage is not the biggest power hog in a data centre, argues Mahesh Vaidya, CEO of data storage specialists ISIT AE. Nevertheless, greening storage can help cut energy bills.

Although servers consume a majority (approximately 50 percent) of data centre power, storage is not far behind, guzzling approximately 13-27 percent. Storage requirements in most data centres are growing at 50-100 percent year-on-year, and due to higher rack densities, arack of storage uses up to 10 times the power it did just a few years ago. Considering these facts, greening storage through various energy saving storage technologies could reduce energy bills dramatically.

In the Middle East and certainly in the UAE, there is another major issue looming – many power-generating authorities are struggling to keep pace with increasing power requirements, further impacting the data centre. For example, several of our enterprise customers have requested ISIT to provide storage technologies that are designed to standards defined by the Green Grid consortium, which helps to address the lack of power from the providers. In a similar context, physical space and cooling in the data centre is also a major consideration addressed by these green standards.

So what’s the answer? We’ve come up with the following 10 recommendations for a greener data centre.

10 strategies for a green data centre

#1: Replace old disk arrays and drives with more energy-efficient, higher capacity arrays and drives. In one case, 11 old disk arrays were replaced with a single new disk array, resulting in 81 percent less power, 93 percent less space, 16 percent higher capacity, reduced complexity and lower management costs.

#2: Consolidate storage. In one example, dozens of file servers across multiple locations were consolidated into one enterprise class NAS at the main data centre with branches accessing this central NAS using WAN and application optimisation technologies.

#3: Improve storage utilisation with thin provisioning and storage virtualisation. In some cases using thin provisioning we have found storage utilisation improve from about 40 percent on an average to more than 80 percent. In addition to this, storage virtualisation could be used to improve utilisation further, especially across multiple disk arrays.

#4: Use solid-state disks instead of FC disks to improve throughput and reduce latency. In some cases, this also reduces power consumption by up to 95 percent over comparable FC disks. It also results in considerable space savings.

#5: Try data deduplication/capacity optimisation. Using these technologies, we have seen 20-30 times disk capacity savings. You could use these technologies right across multiple tiers of storage. Examples are primary storage, secondary storage, backups and archives.

#6: Use high-capacity tape technology. Tape is a zero power media and when it comes to greening storage, tape is a major value-add.

#7: Data classification and migration from high power consumption storage to lower ones (for example FC to SATA and then to tape – in some cases, SATA drives consume half the power of comparable FC drives). Data classification also helps to identify and eliminate duplicate data, orphaned data, unwanted data and data that is stored against corporate policy.

#8: Use flexible clones/snapshots. This capability makes it possible to allocate many individual, writable copies of data in a fraction of the space that would typically be required. For example, take a single snapshot of your primary data, copy that for your DR, backup and compliance, and all of the other copies (copies for testing and development, decision support, etc.) are virtual clones of that original, resulting in tremendous space savings.

#9: Use data protection technologies like dual parity RAID. This enables you to protect against disk failures using fewer drives. For example, compared to RAID 10 (which has 50 percent efficiency), double parity RAID has 86 percent efficiency.

#10: Since servers consume a major part of the total energy consumption in data centres, and most servers are underutilised, we would also strongly recommend server virtualisation. This can drive up server utilisation from an average of 5-15 percent to about 80 percent. In one particular example, approximately 100 servers were consolidated into just 10, having a major impact of power consumption.

For more than 15 years, ISIT has been helping customers address their business issues using a consultative approach, and has pioneered many innovative and state-of-the-art storage technologies in Europe and the Middle East.