Cray-1

The Cray-1 was a supercomputer designed by a team including Seymour Cray (who did the vector register technology) for Cray Research. The first Cray-1 system was installed at Los Alamos National Laboratory in 1976.

Description

The Cray-1A weighed 5.5 tons including the freon refrigeration system. The computer had a 'horseshoe' cross-section in order to reduce wire lengths within the casing; no wire in the system was more than four feet long (1.2 m). It used vector processors and contained 200,000 specialized ECL circuits. The CRAY-1A had a 12.5-nanosecond clock (80 MHz), 8 – 64 word vector registers, and 1 million 64-bit words of high-speed memory (8MB of RAM). It could execute over 80 million floating-point operations per second (80 megaflops), and later Cray-1s increased this to a world-record speed of 133 megaflops.

In 1978, the first standard software package for the Cray-1 was released, consisting of three main products:

• Cray Operating System (COS) (later machines would run UniCOS, Cray's UNIX flavour),
• Cray Assembler Language (CAL), and
• Cray FORTRAN (CFT), the first automatically vectorizing FORTRAN compiler

History

The National Center for Atmospheric Research (NCAR) was Cray Research's first official customer in July 1977, paying US$8.86 million ($7.9 million plus $1 million for the disks). The NCAR machine was decommissioned in January 1989. Priced from $5M to $8M, around 80 Cray-1s of all types were sold.

The Cray-1 was succeeded in 1982 by the 500 megaflops Cray X-MP, the first Cray multi-processing computer. In 1985 the very advanced Cray-2, capable of 1.9 gigaflops peak performance, succeeded the two first models but met a somewhat limited commercial success because of certain problems at producing sustained performance in real-world applications. A more conservatively designed evolutionary successor of the Cray-1 and X-MP models was therefore made, by the name Cray Y-MP, and launched in 1988.

External links

• CRAY-1 Computer System Hardware Reference Manual, Publication No. 2240004 Rev.C 11/77 (http://ed-thelen.org/comp-hist/CRAY-1-HardRefMan/CRAY-1-HRM.html) – first three chapters
  (from the copy at DigiBarn (http://www.digibarn.org)'s collection, digitized and HTML'ized by Ed Thelen)