All these ITIL processes are service-focused; their function is to optimize delivery of business services to business customers. These same principles, however, can be readily applied to IT’s energy consumption. In fact, several industry experts, including IBM and Pacific Gas and Electric (PG&E), have asserted that many IT departments can cut their energy consumption by 40 percent or more. This would do more than just save companies money. According to McKinsey & Company (see “How IT Can Cut Carbon Emissions,” The McKinsey Quarterly, October 2008):
“The rapidly growing carbon footprint associated with information and communications technologies, including laptops and PCs, data centers and computing networks, mobile phones, and telecommunications networks, could make them among the biggest greenhouse gas emitters by 2020. However, our research also suggests that there are opportunities to use these technologies to make the world economy more energy and carbon efficient. An analysis of five groups of abatement opportunities finds that such technologies could help to eliminate 7.8 metric gigatons of greenhouse gas emissions annually by 2020—equivalent to 15 percent of global emissions today and five times more than our estimate of the emissions from these technologies in 2020.”
There also is the real issue of capacity and demand management. There simply won’t be enough energy to support the growth that’s projected in both general and peak IT workloads. IT departments should do everything they can to conserve power and make it available for other critical uses—such as to keep the lights on.
California power utility PG&E is helping IT organizations manage energy capacity by educating its business customers about energy-efficient settings for servers and PCs (sleep mode, etc.), offering rebates on energy-efficient servers, and encouraging data center managers to cool their facilities by simply opening windows when appropriate. This cuts the use and cost of airconditioning, even though chillers may still be needed around racked servers (see Mark Bramfitt, PG&E, “Energy Efficient Leadership for Data Centers and IT,” regions.cmg. org/regions/nccmg, August 2008). Additional cooling is probably not necessary for mainframes.
Everyone knows the rush of warm air that comes from a Wintel server. So it would be desirable to reduce that “rush” by moving workloads onto cooler-running platforms (such as the mainframe) and/or consolidating servers. This also would require driving up the utilization of the processors that remain in service, which is one of the management challenges of green computing.
This highlights the relationship between energy conservation and ITIL processes that addresses capacity and resource utilization. If servers take a lot of power to run and to cool, then it makes sense to have every server running at full capacity. Of course, mainframes provide exceptional value in this regard. Since they’re capable of running at 100 percent utilization, while still providing acceptable performance, they offer the most efficient profile. This is in marked contrast to distributed servers, which experience significant degradations in service as utilization rises unless you fully exploit virtualization.
“In many distributed environments, server utilization levels are considerably lower than those of the mainframe, which typically operate at far higher usage,” wrote CA’s James O’Malley (see “Why Your Company Could Be Going Green Already,” Financial Times, October 2008).
“The latest mainframe utilities can deliver near 100 percent resource uptake,” O’Malley wrote. “In contrast, based on a 24-hour window of observation, comparative values for Intel/Windows and UNIX/RISC platforms were 5 to 10 percent and 15 to 20 percent, respectively.”
Mainframes can provide environmental and economic advantages because they’re architected to permit full utilization while offloading I/O to other processors—a more effective approach than typically found in distributed servers. In fact, because mainframes have been implementing virtualization for such a long time, they have long allowed multiple operating systems to be run in a partitioned environment. This capability is lacking in some distributed virtualization solutions, though this situation has recently improved. However, the rush to exploitation has been disappointing, especially in the U.S.