A Beowulf cluster is a

computer cluster A computer cluster is a set of computers that work together so that they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software. The comp ...

of what are normally identical, commodity-grade computers networked into a small

local area network A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building. By contrast, a wide area network (WAN) not only covers a large ...

with libraries and programs installed which allow processing to be shared among them. The result is a high-performance

parallel computing Parallel computing is a type of computation in which many calculations or processes are carried out simultaneously. Large problems can often be divided into smaller ones, which can then be solved at the same time. There are several different f ...

cluster from inexpensive

personal computer A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or te ...

hardware. The name ''Beowulf'' originally referred to a specific computer built in 1994 by

Thomas Sterling Thomas Sterling (February 21, 1851August 26, 1930) was an American lawyer, politician, and academic who served as a member of the United States Senate and the first dean of the University of South Dakota College of Law. A Republican, he ser ...

and Donald Becker at

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

. The name "Beowulf" comes from the

Old English Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers in the mid-5th ...

epic poem of the same name. No particular piece of software defines a cluster as a Beowulf. Typically only

free and open source software Free and open-source software (FOSS) is a term used to refer to groups of software consisting of both free software and open-source software where anyone is freely licensed to use, copy, study, and change the software in any way, and the sour ...

is used, both to save cost and to allow customisation. Most Beowulf clusters run a

Unix-like A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-li ...

operating system, such as BSD,

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, whi ...

, or Solaris. Commonly used parallel processing libraries include Message Passing Interface (MPI) and Parallel Virtual Machine (PVM). Both of these permit the programmer to divide a task among a group of networked computers, and collect the results of processing. Examples of MPI software include Open MPI or

MPICH MPICH, formerly known as MPICH2, is a freely available, portable implementation of MPI, a standard for message-passing for distributed-memory applications used in parallel computing. MPICH is Free and open source software with some public domai ...

. There are additional MPI implementations available. Beowulf systems operate worldwide, chiefly in support of

scientific computing Computational science, also known as scientific computing or scientific computation (SC), is a field in mathematics that uses advanced computing capabilities to understand and solve complex problems. It is an area of science that spans many disc ...

. Since 2017, every system on the

Top500 The TOP500 project ranks and details the 500 most powerful non- distributed computer systems in the world. The project was started in 1993 and publishes an updated list of the supercomputers twice a year. The first of these updates always coinci ...

list of the world's fastest supercomputers has used Beowulf software methods and a

operating system. At this level, however, most are by no means just assemblages of commodity hardware; custom design work is often required for the nodes (often

blade server A blade server is a stripped-down server computer with a modular design optimized to minimize the use of physical space and energy. Blade servers have many components removed to save space, minimize power consumption and other considerations, whi ...

s), the networking and the cooling systems.

Development

A description of the Beowulf cluster, from the original "how-to", which was published by Jacek Radajewski and Douglas Eadline under the

Linux Documentation Project The Linux Documentation Project (LDP) is a dormant an all-volunteer project that maintains a large collection of GNU and Linux-related documentation and publishes the collection online. It began as a way for hackers to share their documentation ...

in 1998:

Operating systems

a number of

Linux distribution A Linux distribution (often abbreviated as distro) is an operating system made from a software collection that includes the Linux kernel and, often, a package management system. Linux users usually obtain their operating system by downloading one ...

s, and at least one BSD, are designed for building Beowulf clusters. These include: *

MOSIX MOSIX is a proprietary distributed operating system. Although early versions were based on older UNIX systems, since 1999 it focuses on Linux clusters and grids. In a MOSIX cluster/grid there is no need to modify or to link applications with an ...

, geared toward computationally intensive, IO-low applications * ClusterKnoppix, based on

Knoppix KNOPPIX ( ) is an operating system based on Debian designed to be run directly from a CD / DVD ( Live CD) or a USB flash drive (Live USB), one of the first live operating system distributions (just after Yggdrasil Linux). Knoppix was develop ...

* Kerrighed *

Rocks Cluster Distribution Rocks Cluster Distribution (originally NPACI Rocks) is a Linux distribution intended for high-performance computing (HPC) clusters. It was started by National Partnership for Advanced Computational Infrastructure and the San Diego Supercompute ...

DragonFly BSD DragonFly BSD is a free and open-source Unix-like operating system forked from FreeBSD 4.8. Matthew Dillon, an Amiga developer in the late 1980s and early 1990s and FreeBSD developer between 1994 and 2003, began working on DragonFly BSD ...

* Quantian, a live DVD with scientific applications, based on Knoppix and ClusterKnoppix * Kentucky Linux Athlon Testbed * PelicanHPC, based on Debian Live A cluster can be set up by using Knoppix bootable CDs in combination with

OpenMosix openMosix was a free cluster management system that provided single-system image (SSI) capabilities, e.g. automatic work distribution among nodes. It allowed program processes (not threads) to migrate to machines in the node's network that w ...

. The computers will automatically link together, without need for complex configurations, to form a Beowulf cluster using all CPUs and

RAM Ram, ram, or RAM may refer to: Animals * A male sheep * Ram cichlid, a freshwater tropical fish People * Ram (given name) * Ram (surname) * Ram (director) (Ramsubramaniam), an Indian Tamil film director * RAM (musician) (born 1974), Dutch * ...

in the cluster. A Beowulf cluster is scalable to a nearly unlimited number of computers, limited only by the overhead of the network. Provisioning of operating systems and other software for a Beowulf Cluster can be automated using software, such as

Open Source Cluster Application Resources Open Source Cluster Application Resources (OSCAR) is a Linux-based software installation for high-performance cluster computing. OSCAR allows users to install a Beowulf type high performance computing cluster. See also * TORQUE Resource Manager ...

. OSCAR installs on top of a standard installation of a supported Linux distribution on a cluster's head node.

References

Bibliography

* ''Beowulf Cluster Computing With Windows'' by Thomas Lawrence Sterling 2001 MIT Press * ''Beowulf Cluster Computing With Linux'' by Thomas Lawrence Sterling 2001 MIT Press

External links

The Beowulf Cluster Site
*
A detailed description of building a Beowulf cluster
{{Authority control Cluster computing Parallel computing Job scheduling NASA spin-off technologies Unix software