The Stone Soupercomputer was a Beowulf

Beowulf (computing)

A Beowulf cluster is a computer cluster of what are normally identical, commodity-grade computers networked into a small local area network with libraries and programs installed which allow processing to be shared among them...

-style computer cluster built at the US Oak Ridge National Laboratory

Oak Ridge National Laboratory

Oak Ridge National Laboratory is a multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle. ORNL is the DOE's largest science and energy laboratory. ORNL is located in Oak Ridge, Tennessee, near Knoxville...

 in the late 1990s.

History

A group of lab employees including William W. Hargrove and Forrest M. Hoffman had applied for a grant to build a cluster in 1996, but it was rejected.
Software was patterned after the Beowulf

Beowulf (computing)

A Beowulf cluster is a computer cluster of what are normally identical, commodity-grade computers networked into a small local area network with libraries and programs installed which allow processing to be shared among them...

 project pioneered by NASA

NASA

The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

. They decided to build a cluster anyway, using desktop personal computer

Personal computer

A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...

s that had been discarded as being too slow. The name was derived from the story of Stone soup

Stone soup

Stone Soup is an old folk story in which hungry strangers persuade local people of a town to give them food. It is usually told as a lesson in cooperation, especially amid scarcity. In varying traditions, the stone has been replaced with other common inedible objects, and therefore the fable is...

.
The developers used freely available and open source software such as Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 operating system, the Parallel Virtual Machine

Parallel Virtual Machine

The Parallel Virtual Machine is a software tool for parallel networking of computers. It is designed to allow a network of heterogeneous Unix and/or Windows machines to be used as a single distributed parallel processor. Thus large computational problems can be solved more cost effectively by...

 toolkit and the Message Passing Interface

Message Passing Interface

Message Passing Interface is a standardized and portable message-passing system designed by a group of researchers from academia and industry to function on a wide variety of parallel computers...

 library.

By early 1997 the first applications were running on the cluster. By May 2001 it had 133 nodes.
They included Intel 80486

Intel 80486

The Intel 80486 microprocessor was a higher performance follow up on the Intel 80386. Introduced in 1989, it was the first tightly pipelined x86 design as well as the first x86 chip to use more than a million transistors, due to a large on-chip cache and an integrated floating point unit...

 and Pentium

Pentium

The original Pentium microprocessor was introduced on March 22, 1993. Its microarchitecture, deemed P5, was Intel's fifth-generation and first superscalar x86 microarchitecture. As a direct extension of the 80486 architecture, it included dual integer pipelines, a faster FPU, wider data bus,...

-based machines and a few DEC Alpha

DEC Alpha

Alpha, originally known as Alpha AXP, is a 64-bit reduced instruction set computer instruction set architecture developed by Digital Equipment Corporation , designed to replace the 32-bit VAX complex instruction set computer ISA and its implementations. Alpha was implemented in microprocessors...

 workstations. Low-cost Ethernet

Ethernet

Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....

 networking was used for interconnection instead of any special-purpose network.
The cluster was the subject of an article in Scientific American

Scientific American

Scientific American is a popular science magazine. It is notable for its long history of presenting science monthly to an educated but not necessarily scientific public, through its careful attention to the clarity of its text as well as the quality of its specially commissioned color graphics...

magazine in 2001.
Many applications were developed on this system that could then be deployed on other, faster clusters. The stone cluster was no longer in use by August 2003.
This approach was used as a model for other educational cluster projects.