Notice: Active support for this tool is currently discontinued. The source code is provided below for the brave souls who would like to hack away at it.
Martin Dimitrov, Carl Strickland, Seung-Woo Kim, Karthik Kumar, Kshitij Doshi
Intel® Power Governor (power_gov) is a software utility and library, which allows developers to (a) monitor power and (b) regulate power at very fine time granularities (few tens of milliseconds). Power monitoring/control is available for the package, core, graphics, uncore and DRAM domains, as illustrated in Figure 1 below. The tool is self-contained, easy to use, and available on Intel® Xeon® E5 series processors based on Intel® microarchitecture code-named Sandy Bridge EP/EN/E, 2nd Generation Intel® Core™ and newer processors. As a library, power_gov allows developers to incorporate power monitoring/control into their own custom and dynamic solutions tailored to the needs of their application.
Software power meter: power_gov can be used to report power consumption on the different power planes. The example in Figure 2 shows power_gov executing on a two socket Intel® Xeon® Processor E5-based machine, and reporting the average power consumption of the package, core, uncore and DRAM for each socket at 1 second intervals.
Figure 2. power_gov reporting power consumption at 1-second intervals for package, core, uncore, DRAM domains on a two-socket system.
Figure 3. Using power_gov to optimize for a power/performance target.
Figure 4. Using the power_gov library in order to design dynamic power/performance optimization solutions.
 V. Anagnostopoulou, M. Dimitrov, K. Doshi, “SLA-Guided Energy Savings for Enterprise Servers”, ISPASS 2012 poster, full version to appear in ITJ 2012