A recent study on real-world server utilization found that upwards of 30 percent of data center servers are ‘comatose’ meaning they produced no useful work within the last six months. A sad state of affairs made all the more worse by the industry’s poor average utilization rates that although somewhat improved since the 2007 EPA Report to Congress still range on the order of 8 to 15 percent. That means an awful lot of energy is being wasted in data centers around the world that could easily be saved through lower server idle power levels.
Today Vertiv proposes a new standard – the 10 Minus server idle energy standard. A standard modeled off of the very successful 80 Plus power supply specification originally developed by Ecos Consulting and championed by the Climate Savers Computing Initiative and a host of other leading hardware vendors, OEMs, data center owners / operators as well as the EPA/DOE and EPRI. The 80 Plus specification for embedded server power supplies (and other IT/networking devices) has become so well entrenched within our industry that it is almost impossible to purchase a new piece of an IT kit that doesn’t achieve 90 percent efficiency on AC to DC power conversion.
With 10 Minus, we now address the server’s idle energy performance with the initial target established at 10 percent of full rated power when the server is idle. Further like the 80 Plus specification we introduce Silver, Gold, and Platinum ratings to recognize those devices capable of exceeding the minimum 10 percent level with Silver for those below 8.5 percent, Gold for those below 7.5 percent, and Platinum for those below 5 percent. As with the 80 Plus program these levels will be revisited every three years and adjusted downward once 50 percent of the qualified devices achieve Gold or better performance. Of course we could just turn the servers OFF but data shows us that this idea is not palatable to the vast majority of IT and data center professionals.
Therefore forcing idle power to drop to 10 percent or lower appears to be the most viable and achievable solution. Let’s take a look at what the new 10 Minus specification would mean for the average data center. We will apply a few conservative assumptions to our model so your potential savings will likely be greater.
Applying the 10 Minus specification to a model data center with 500 servers each rated at 300 watts under ‘normal’ operation and 100 watts when idle (you should be so lucky) with a better-than-average comatose server rate of only 20 percent would demonstrate:
- Without 10 Minus
Comatose servers alone consume 100 watts x 100 comatose servers x 8760 hours/year for a total of 87,600 kWh/year - With 10 Minus – Instant Savings in Excess of 60,000 kWH/year
A minimum standard of 10 percent would be 30 watts x 100 comatose servers x 8760 hours/year for a total of 26,280 kWh/year
However the total savings from applying the 10 Minus standard across the entire IT kit would be significantly higher as our average server utilization rate even if as high as 50 percent means the rest of the time we would see forced savings through reduced idle energy consumption. Using the above model data center our 500 servers are idle at least 50 percent of the time with idle energy consumption of:
- Without 10 Minus
100 watts x 400 servers (backed out comatose servers as accounted for above) x 4380 hours/year = 175,200 kWh/year - With 10 Minus – Net Savings in Excess of 120,000 kWh
The numbers improve significantly to 30 watts x 400 servers x 4380 hours/year = 52,500 kWh/year
By adding the production and comatose server energy savings together, this model data center would realize energy savings in excess of 180,000 kWh a year on a modest deployment of 500 production servers. Extrapolated across a larger enterprise, cloud, or Hyperscale environment and the savings would be monumental.
How do we turn the 10 Minus concept into an industry standard? Climate Savers is now gone and The Green Grid has taken over the mantle. Currently The Green Grid has an open activity request to address comatose servers. Both SPEC and the EPA under their Energy Star® initiatives are slowly addressing the power profile of servers albeit with industry pushback when it comes to idle performance. Perhaps EPRI, along with their EMEA, Japan, and Asia-Pac counterparts are in the best position to drive this standard as the electrical utilities would greatly appreciate an instant and permanent 10 to 40 percent energy reduction from an individual data center with something as simple as deploying 10 Minus certified servers and IT kits.
As many experts within the data center community say: ‘We need to start working on the one side of PUE, the IT load.’ 10 Minus is one easy approach to deploy to address the one side of PUE while also reducing the negative impact of comatose servers on data center energy consumption and productivity per watt.
Let’s face it, if our motor vehicles operated with idle performance like servers there likely wouldn’t be enough oil capacity to quench their thirst. And today we have numerous motor vehicles that not only idle on less than 1 percent of normal operation energy use but also auto-shutoff when the vehicle is stopped. It is time we initiated a standard like 10 Minus to address the deficiencies in server idle performance.
Come visit with me at the upcoming Green Grid Forum 2016 in Seattle, WA, USA, March 8 and 9 where we can discuss this in more detail or post your comments below.
