First launched in 1982, this system was capable of 500 megaflops and was the first multi-processor supercomputer. It ran the company’s first operating system based on UNIX, UNICOS. It was the descendent of the Cray 1, and was built by Cray Research. By 1986, the system’s XMP-22 model sported 4 processors and had a theoretical peak performance of 800 megaflops. It’s speed was more than double that of comparative machines. The XMP was Cray’s most successful machine.