The Cray APP was a parallel computer sold by Cray Research from 1992 onwards. It was based around the Intel i860

Intel i860

The Intel i860 was a RISC microprocessor from Intel, first released in 1989. The i860 was one of Intel's first attempts at an entirely new, high-end instruction set since the failed Intel i432 from the 1980s...

 microprocessor

Microprocessor

A microprocessor incorporates the functions of a computer's central processing unit on a single integrated circuit, or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and...

 and could be configured with up to 84 processors. The architecture was based around "computational nodes" of 12 processors interconnected by a shared bus, with multiple nodes connected to each other, memory and I/O nodes via an 8×8 crossbar switch

Crossbar switch

In electronics, a crossbar switch is a switch connecting multiple inputs to multiple outputs in a matrix manner....

.

The APP was marketed as a "matrix co-processor" system and required a SPARC

SPARC

SPARC is a RISC instruction set architecture developed by Sun Microsystems and introduced in mid-1987....

-based host system to operate, such as the Cray S-MP

Cray S-MP

The Cray S-MP was a multiprocessor server computer sold by Cray Research from 1992 to 1993. It was based around the Sun SPARC microprocessor architecture and could be configured with up to eight 66 MHz BIT B5000 processors. Optionally, a Cray APP matrix co-processor cluster could be added to an...

. Connection to the host system was via VMEbus

VMEbus

VMEbus is a computer bus standard, originally developed for the Motorola 68000 line of CPUs, but later widely used for many applications and standardized by the IEC as ANSI/IEEE 1014-1987. It is physically based on Eurocard sizes, mechanicals and connectors , but uses its own signalling system,...

 or HiPPI

HIPPI

HIPPI is a computer bus for the attachment of high speed storage devices to supercomputers. It was popular in the late 1980s and into the mid-to-late 1990s, but has since been replaced by ever-faster standard interfaces like SCSI and Fibre Channel.The first HIPPI standard defined a 50-wire...

. A fully configured APP had a peak performance of 6.7 (single-precision) gigaflops.

The APP was originally designed by FPS Computing as the FPS MCP-784. FPS were acquired by Cray Research in 1991, becoming Cray Research Superservers Inc., and the MCP-784 was relaunched by Cray in 1992 as the APP.