The US Department of Energy's Pacific Northwest National Laboratory (PNNL) has acquired a Cray XMT supercomputer to help with its data-intensive research.
The Cray XMT system has a 'massively multithreaded' architecture with large global memory. In this application it will be used to model and analyse grids of electrical power, but it could also be used for bioinformatics and business analysis.
The random and unpredictable data access required by these efforts means they do not run well on conventional computer systems, where performance is determined mainly by the speed at which the memory can deliver information to the microprocessor. In many large-scale applications of this kind, the processor is idle 80 to 90 percent of the time while waiting for data from memory.
The Cray XMT system is built to overcome memory bottlenecks with each processor able to handle 128 independent portions of a program, that can work by themselves or concurrently with other 'threads'. Overall, the entire system can handle hundreds of thousands of these threads.
