In May last year, amid growing concerns about power efficiency, the Standard Performance Evaluation Corporation (SPEC) announced that it had created a new committee to oversee the development of a power-performance benchmark. Over a year and a half later, SPEC says it has finally completed work on the benchmark, which it dubs SPECpower_ssj2008.
According to SPEC, SPECpower_ssj2008 is the very first industry-standard benchmark designed to measure power consumption in relation to performance for server systems. The company explains its methodology as follows:
SPECpower_ssj2008 reports power consumption for servers at different performance levels – from 100-percent to idle in 10-percent segments – over a set period of time. The graduated workload recognizes the fact that processing loads and power consumption on servers vary substantially over the course of days or weeks. To compute a power-performance metric across all levels, measured transaction throughputs for each segment are added together, then divided by the sum of the average power consumed for each segment. The result is a figure of merit called "overall ssj_ops/watt."
The benchmark workload represents typical server-side Java business applications. The workload is scalable, multi-threaded, portable across a wide range of operating environments, and economical to run. It exercises CPUs, caches, memory hierarchy, and the scalability of shared memory processors (SMPs), as well as implementations of the Java Virtual Machine (JVM), JIT (just in time) compiler, garbage collection, threads, and some aspects of the operating system.
Running the benchmark requires a minimum of two networked computers, a power analyzer, and a temperature sensor. One of the systems is the "system under test," or SUT, while the other is a control machine. SPEC already has a list of preliminary results handy. According to the list, the system to score highest so far is an Intel Xeon E5450-powered HP Proliant DL160 G5 server, which scored 698. The system to score lowest is another Intel machine, this time based on a 3.6GHz Netburst-based Xeon, which scored just 87.4.
SPEC says SPECpower_ssj2008 is "available immediately" at a price of $1,600, although discounts are offered to non-profit and educational organizations. More information is available on this page.