As global IT power consumption becomes a pressing concern, IT providers are scrambling to create or configure systems for maximum energy efficiency. But the only way to determine true energy efficiency is to have a common benchmark that takes into account not just power savings, but also system performance. For example, one system configuration may offer the most power savings, but it may run much more slowly and therefore use more total energy.
The common benchmark should also take into account the power used by the whole system rather than just its individual components. A benchmark focusing only on CPU, for example, would fail to account for power used by other components such as disks and memory, which comprise a significant portion of the total power used.
With a team from Stanford University, HP researchers developed JouleSort (named for the Joule, a standard unit of energy), an extension of the Sort Benchmarks that are traditionally used to measure performance/cost performance of computer systems.
JouleSort measures system performance when sorting a fixed, but large amount of data. This workload exercises all core components of a system and is portable -- meaning it is capable of evaluating the energy efficiency of a wide range of computer systems. JouleSort helps system designers understand the bottlenecks in achieving energy efficiency and points out trends in energy-efficient designs.
The team applied this benchmark to create a new system that was nearly four times more energy efficient than the previous estimated best system from 2006. This work was first presented at a conference in China in June 2007.
Since then, JouleSort has been adopted by the database community’s Sort Committee that administers other sort benchmarks for pure performance and cost.
Longer term, researchers are exploring a way to measure the environmental impact of the entire IT lifecycle – from the raw materials extracted to build the machine to its manufacturing to its recycling and potential reuse.