Cray YMP Model D Range
The Cray-YMP range of computers were manufactured from 1989 until 1994. Around 200 of these machines were manufactured, and many customers migrated their workload from the Cray-XMP to a Cray-YMP. Like the Cray-XMP, the Cray-YMP were available with multiple processor configurations of 2, 4, 8 processors. The early machines used the same Model-D Input-Output subsystem as the XMP range. The Cray-YMP runs on UNICOS a UNIX operating system.
The CRAY Y-MP CPUs and memory, one I/O Subsystem and the SSO are connected in a Y shaped configuration. The rectangular CRAY Y-MP mainframe chassis, which occupies 98 square feet (9.2 square meters) of floor space, contains the CPU and memory modules, power supplies, power distribution units, and coolant hoses. Each lOS consists of four vertical columns arranged in a 90° arc occupying 15 square feet (1.4 square meters) of floor space. One lOS is attached directly to the mainframe chassis and forms one arm of the Y configuration. The optional second lOS can be up to 9.5 feet (2.9 meters) from the mainframe cabinet. The SSD cabinet also consists of four columns arranged in a 90°arc occupying 15 square feet (1.4 square meters) of floor space. It forms the other arm of the Y configuration.