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 newes ...

of 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, campus, or building, and has its network equipment and interconnects locally managed. LANs facilitate the distribution of da ...

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

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

cluster from inexpensive

personal computer A personal computer, commonly referred to as PC or computer, is a computer designed for individual use. It is typically used for tasks such as Word processor, word processing, web browser, internet browsing, email, multimedia playback, and PC ...

hardware.

Original

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 agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

. They named it after the

Old English Old English ( or , or ), 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 developed from the languages brought to Great Britain by Anglo-S ...

epic poem, '' Beowulf''.

Systems

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 software available under a Software license, license that grants users the right to use, modify, and distribute the software modified or not to everyone free of charge. FOSS is an inclusive umbrella term ...

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

Unix-like A Unix-like (sometimes referred to as UN*X, *nix 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 Uni ...

operating system, such as

BSD The Berkeley Software Distribution (BSD), also known as Berkeley Unix or BSD Unix, is a discontinued Unix operating system developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berkeley, beginni ...

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

, or

Solaris Solaris is the Latin word for sun. It may refer to: Arts and entertainment Literature, television and film * ''Solaris'' (novel), a 1961 science fiction novel by Stanisław Lem ** ''Solaris'' (1968 film), directed by Boris Nirenburg ** ''Sol ...

. Commonly used parallel processing libraries include

Message Passing Interface The Message Passing Interface (MPI) is a portable message-passing standard designed to function on parallel computing architectures. The MPI standard defines the syntax and semantics of library routines that are useful to a wide range of use ...

(MPI) and

Parallel Virtual Machine Parallel Virtual Machine (PVM) 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 computa ...

(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 Open MPI is a Message Passing Interface (MPI) library project combining technologies and resources from several other projects (FT-MPI, LA-MPI, LAM/MPI, and PACX-MPI). It is used by many TOP500 supercomputers including Roadrunner, which was th ...

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 domain c ...

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

scientific computing Computational science, also known as scientific computing, technical computing or scientific computation (SC), is a division of science, and more specifically the Computer Sciences, which uses advanced computing capabilities to understand and s ...

. Since 2017, every system on the

Top500 The TOP500 project ranks and details the 500 most powerful non-distributed computing, 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 ...

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, wh ...

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 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 with ...

in 1998:

Operating systems

a number of

Linux distribution A Linux distribution, often abbreviated as distro, is an operating system that includes the Linux kernel for its kernel functionality. Although the name does not imply product distribution per se, a distro—if distributed on its own—is oft ...

s, and at least one

, 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 any ...

, geared toward computationally intensive, IO-low applications *

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 ...

, latest 2017 *

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 in ...

OS, latest 2022 *

Quantian ''Quantian OS'' was a remastering of Knoppix/Debian for computational sciences. The environment was self-configuring and directly bootable CD/DVD that turns any PC or laptop (provided it can boot from cdrom/DVD) into a Linux workstation. Quantian ...

OS latest 2006, a live DVD with scientific applications, remastered from

Knoppix Knoppix, stylized KNOPPIX ( ), is an operating system based on Debian designed to be run directly from a CD or DVD (Live CD) or a USB flash drive ( Live USB). It was first released in 2000 by German Linux consultant Klaus Knopper, and was one ...

* Kentucky Linux Athlon Testbed, physical installation at University of Kentucky The following are no longer maintained: *

Kerrighed Kerrighed is an open source single-system image (SSI) cluster software project. The project started in October 1998 at the Paris research group The French National Institute for Research in Computer Science and Control. From 2006 to 2011, the pro ...

(EOL: 2013) *

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 ...

(EOL: 2008), forked from MOSIX *

ClusterKnoppix 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 wo ...

OS, forked from

* PelicanHPC OS latest 2016, based on

Debian Live Debian () is a free and open source Linux distribution, developed by the Debian Project, which was established by Ian Murdock in August 1993. Debian is one of the oldest operating systems based on the Linux kernel, and is the basis of many o ...

A cluster can be set up by using Knoppix bootable CDs in combination with

. 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 most commonly refers to: * A male sheep * Random-access memory, computer memory * Ram Trucks, US, since 2009 ** List of vehicles named Dodge Ram, trucks and vans ** Ram Pickup, produced by Ram Trucks Ram, ram, or RAM may also ref ...

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