The Green Computing Performance Index (GCPI)

 

Existing Benchmarks Reach Their Limit

For years, the LINPACK benchmark has been widely used as the tool for measuring a computer system’s floating point performance. For example, the High Performance LINPACK (HPL) benchmark is used as the primary performance indicator for ranking the world’s 500 fastest computers. Despite its high profile status as the foundation of the Top500 list, use of the LINPACK benchmark alone to predict a computer’s real-world, delivered performance was limiting due to its singular focus on stressing only the CPU component of an HPC system.

The 2003 release of the High Performance Computing Challenge (HPCC) suite of benchmarks reflected the HPC community’s need for a tool to evaluate a system’s performance across a broad spectrum of application areas. The HPCC Benchmark suite aims to stress the major components of a HPC system, including the processor, memory subsystem, and interconnect, and so predict real-world application performance.

The Need for Green IT

In recent years, the growing demand for power to drive data centers has become a serious global issue. Commercial and technical computing centers alike face key challenges in coping with the ever-increasing demand for computing power:

  • Electrical power constraints: caps on the amount of power available to the data center, as racks and racks of traditional cluster systems with faster clock speeds are added to the facilities.
  • Cooling constraints and costs: computers need to be kept cool to function. For every extra watt needed to power computing, up to another watt is required for cooling. Cooling equipment often takes as much space as the computers themselves.
  • Space constraints: data centers are simply running out of floor space as racks of cluster systems and the necessary cooling equipment proliferate.

Over the past year, two efforts in the HPC Community were initiated to incorporate energy efficiency into the context of supercomputer performance measurement. The first was the launch of the Green500 list, which ranked the most energy-efficient supercomputers in the world. The second occurred in June 2008, when the Top500 list began to report system power data.

While these efforts were positive steps forward, they were inherently limited by their use of LINPACK as the underlying measure of performance.

The Green Computing Performance Index - HPC’s New Standard

SiCortex, in cooperation with industry experts, has proposed a more inclusive metric for comparing energy efficiency in High-Productivity Computing segment, the Green Computing Performance Index (GCPI). The GCPI analyzes computing performance-per-kWatt across a spectrum of industry-standard benchmarks, providing organizations with much-needed guidance in the era of out-of-control data center energy consumption.

The GCPI is the first index to measure, analyze and rank computers on a broad range of performance metrics relative to energy consumed. It provides data center managers with a business tool to help them compare delivered performance-per-watt among leading HPC systems and make more informed decisions.

The GCPI is derived from a straightforward calculation that examines a representative sample of established high-productivity computers, and catalogues each according to HPCC industry benchmarks and energy consumption data. The index will expand over time as more data becomes publicly available.