Editing Parallel Virtual Machine (section)

{{Short description|Software tool for parallel networking of computers}}
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{{Infobox software
| logo                   = <!-- [[File: ]] -->
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| author                 = [[Oak Ridge National Laboratory]]
| developer              = [[University of Tennessee]]
| released               = 1989 <!-- {{Start date|YYYY|MM|DD}} -->
| discontinued           =
| latest release version = 3.4.6
| latest release date    = {{Start date and age|2009|02|02}}<ref>[http://www.netlib.org/pvm3/RELEASE_NOTES.txt Release Notes]</ref>
| latest preview version =
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| frequently updated     =
| programming language   = [[C (programming language)|C]]
| operating system       = Windows and Unix
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| license                = [[BSD licenses|BSD]], [[GNU General Public License|GPL]]
| website                = https://www.epm.ornl.gov/pvm/pvm_home.html
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'''Parallel Virtual Machine''' ('''PVM''') is a [[computer software|software]] tool for parallel networking of [[computer]]s. It is designed to allow a [[computer network|network]] of heterogeneous Unix and/or Windows machines to be used as a single distributed [[parallel processor]].<ref>{{FOLDOC|Parallel+Virtual+Machine}}</ref> Thus large computational problems can be solved more cost effectively by using the aggregate power and memory of many computers. The software is very portable; the source code, available free through [[netlib]], has been compiled on everything from [[laptop]]s to [[Cray]]s.<ref name=PvmHome>{{cite web|url=http://www.csm.ornl.gov/pvm/|title=Parallel Virtual Machine (PVM) Homepage}}</ref>

PVM enables users to exploit their existing computer hardware to solve much larger problems at less additional cost. PVM has been used as an educational tool to teach [[parallel programming]] but has also been used to solve important practical problems.<ref name=PvmHome/> It was developed by the [[University of Tennessee]], [[Oak Ridge National Laboratory]] and [[Emory University]]. The first version was written at ORNL in 1989, and after being rewritten by University of Tennessee, version 2 was released in March 1991. Version 3 was released in March 1993, and supported [[fault tolerance]] and better [[portability (computer science)|portability]].

PVM was a step towards modern trends in [[distributed processing]] and [[grid computing]] but has, since the mid-1990s, largely been supplanted by the much more successful [[Message Passing Interface|MPI]] standard for message passing on parallel machines.   PVM is [[free software]], released under both the [[BSD License]] and the [[GNU General Public License]].