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- From: shane@ERC.MsState.Edu (Shane Hebert)
- Newsgroups: comp.parallel.mpi,comp.answers,news.answers
- Subject: Message Passing Interface (MPI) FAQ
- Supersedes: <mpi-faq-4-1999@ERC.MsState.Edu>
- Followup-To: poster
- Date: 02 May 1999 06:00:36 GMT
- Organization: Mississippi State University NSF Engineering Research
- Center for Computational Field Simulation
- Lines: 532
- Approved: news-answers-request@MIT.EDU
- Expires: 06 Jun 1999 06:00:36 GMT
- Message-ID: <mpi-faq-5-1999@ERC.MsState.Edu>
- NNTP-Posting-Host: titan.erc.msstate.edu
- Summary: This posting contains a list of common questions (and their
- answers) about the Message Passing Interface standard (also
- known as MPI).
- Keywords: FAQ, MPI, Parallel & Distributed Computing
- Originator: shane@ERC.MsState.Edu
- Xref: senator-bedfellow.mit.edu comp.parallel.mpi:5315 comp.answers:36016 news.answers:157054
-
- Archive-Name: mpi-faq
- Posting-Frequency: monthly
-
- Message Passing Interface (MPI) FAQ
- Shane Hebert, shane@erc.msstate.edu
- Last modified: Tues Jan 13 13:58:32 1997
-
- This is the list of Frequently Asked Questions about the MPI (Message
- Passing Interface) standard, a set of library functions for message
- passing. For a list of the latest changes to this document, see sec-
- tion ``What's New?''. Comments on the FAQ are welcome. See question
- ``Formats'' for details of where to get the PostScript, Emacs Info,
- HTML, and text versions of this document.
-
- 1. Introduction and General Information
-
-
- This FAQ attempts to answer basic questions regarding MPI. Pointers
- to further information on MPI are included for those wishing to know
- more.
-
-
-
- 1.1. What is MPI?
-
- MPI stands for Message Passing Interface. The goal of MPI, simply
- stated, is to develop a widely used standard for writing message-
- passing programs. As such the interface attempts to establish a
- practical, portable, efficient, and flexible standard for message
- passing.
-
- In designing MPI the MPI Forum sought to make use of the most
- attractive features of a number of existing message passing systems,
- rather than selecting one of them and adopting it as the standard.
- Thus, MPI has been strongly influenced by work at the IBM T. J. Watson
- Research Center, Intel's NX/2, Express, nCUBE's Vertex, p4, and
- PARMACS. Other important contributions have come from Zipcode, Chimp,
- PVM, Chameleon, and PICL.
-
- The main advantages of establishing a message-passing standard are
- portability and ease-of-use. In a distributed memory communication
- environment in which the higher level routines and/or abstractions are
- build upon lower level message passing routines the benefits of
- standardization are particularly apparent. Furthermore, the
- definition of a message passing standard provides vendors with a
- clearly defined base set of routines that they can implement
- efficiently, or in some cases provide hardware support for, thereby
- enhancing scalability.
-
- Source: MPI Document - <http://www.mpi-
- forum.org/docs/mpi-11-html/mpi-report.html>.
-
-
-
- 1.2. What is the MPI Forum?
-
- Message Passing Interface Forum
-
- The Message Passing Interface Forum (MPIF), with participation from
- over 40 organizations, met from November 1992 to April 1994 to discuss
- and define a set of library interface standards for message passing.
- Version 1.0 of the standard was released on May 5, 1994. Beginning in
- March, 1995, the MPIF reconvened to correct errors and make
- clarifications in the MPI document of May 5, 1994. These discussions
- resulted in Version 1.1 (dated June, 1995) which contained only minor
- changes from Version 1.0. MPI-2 meetings began April, 1995 and met
- every six weeks until April 25, 1997. At the end of that meeting, the
- entire MPI-2 Document was unanimously accepted by all voting
- institutions. For more information on the MPI-2 process, see the
- section on the MPI-2 effort (Section ``MPI-2'').
-
- The MPIF is not sanctioned or supported by any official standards
- organization.
-
- Source: MPI Document - <http://www.mpi-
- forum.org/docs/mpi-11-html/mpi-report.html>.
-
-
-
- 1.3. A Brief History of MPI
-
- The MPI standardization effort involved about 60 people from 40
- organizations mainly from the United States and Europe. Most of the
- major vendors of concurrent computers were involved in MPI, along with
- researchers from universities, government laboratories, and industry.
- The standardization process began with the Workshop on Standards for
- Message Passing in a Distributed Memory Environment, sponsored by the
- Center for Research on Parallel Computing, held April 29-30, 1992, in
- Williamsburg, Virginia. At this workshop the basic features essential
- to a standard message passing interface were discussed, and a working
- group established to continue the standardization process.
-
- A preliminary draft proposal, known as MPI1
- <ftp://netlib2.cs.utk.edu/mpi/mpi1.ps>, was put forward by Dongarra,
- Hempel, Hey, and Walker in November 1992, and a revised version was
- completed in February 1993. MPI1 embodied the main features that were
- identified at the Williamsburg workshop as being necessary in a
- message passing standard. Since MPI1 was primarily intended to promote
- discussion and ``get the ball rolling,'' it focused mainly on point-
- to-point communications. MPI1 brought to the forefront a number of
- important standardization issues, but did not include any collective
- communication routines and was not thread-safe.
-
- In November 1992, a meeting of the MPI working group was held in
- Minneapolis, at which it was decided to place the standardization
- process on a more formal footing, and to generally adopt the
- procedures and organization of the High Performance Fortran Forum.
- Subcommittees were formed for the major component areas of the
- standard, and an email discussion service established for each. In
- addition, the goal of producing a draft MPI standard by the Fall of
- 1993 was set. To achieve this goal the MPI working group met every 6
- weeks for two days throughout the first 9 months of 1993, and
- presented the draft MPI standard at the Supercomputing 93 conference
- in November 1993. These meetings and the email discussion together
- constituted the MPI Forum, membership of which was and continues to be
- open to all members of the high performance computing community.
-
- Beginning in March, 1995, the MPIF reconvened to correct errors and
- make clarifications in the MPI document of May 5, 1994. These
- discussions resulted in Version 1.1 (dated June, 1995) which contained
- only minor changes from Version 1.0. MPI-2 meetings began April, 1995
- and met every six weeks until April 25, 1997. At this meeting, the
- MPI-2 Document was unanimously accepted. For more information on the
- MPI-2 process, see the section on the MPI-2 effort (Section
- ``MPI-2'').
-
- Source: MPI Document - <http://www.mpi-
- forum.org/docs/mpi-11-html/mpi-report.html>.
-
-
-
- 1.4. The MPI-1 Document
-
- There are two versions of the MPI document: version 1.0 (dated May 5,
- 1994) and version 1.1 (dated June, 1995).
- o Version 1.1 (June 12, 1995)
-
- Version 1.1 (June 12, 1995) of the MPI Document is available on-
- line as HTML at <http://www.mpi-forum.org/docs/mpi-11-html/mpi-
- report.html>. It is also available as postscript from the
- following locations:
-
- o <http://www.mpi-forum.org/docs/mpi-11.ps>
-
- o <ftp://ftp.erc.msstate.edu/pub/mpi/docs/mpi-report1.1.ps>
-
- A compressed version of the postscript document is available from
-
- o <http://www.mpi-forum.org/docs/mpi-11.ps.Z>
-
- o <ftp://ftp.erc.msstate.edu/pub/mpi/docs/mpi-report1.1.ps.Z>
-
-
- o Version 1.0 (May 5, 1994)
-
- The official postscript version of the document can be obtained
- from netlib at ORNL by sending a mail message to netlib@ornl.gov
- with the message "send mpi-report.ps from mpi".
-
- It may also be obtained by anonymous ftp from the following sites:
-
- o <ftp://netlib2.cs.utk.edu/mpi/mpi-report.ps>
-
- o <ftp://ftp.erc.msstate.edu/pub/mpi/docs/mpi-report.ps.Z>
-
- o <http://www.mpi-forum.org/docs/mpi-10.ps>
-
- o <http://www.mpi-forum.org/docs/mpi-10.ps.Z>
-
-
-
- 2. Online Resources
-
-
-
- 2.1. WWW Sites
-
-
-
-
- Official Message Passing Interface (MPI) Homepage <http://www.mpi-
- forum.org>
- MPI-Forum.Org is the official homesite of the MPI Forum and
- contains official Forum documents and the MPI Standard documents
- in a variety of formats.
-
-
- Argonne MPI Homepage <http://www.mcs.anl.gov/mpi>
- The Argonne National Lab MPI Homepage has a large collection of
- accumulated information about MPI, including pointers to
- implementations and tutorials by the site maintainers and
- others.
-
-
- Official MPICH Homepage <http://www.mcs.anl.gov/mpich>
- The Official MPICH Homepage has buttons for downloading MPICH in
- various forms, buglists, patchfiles, and other MPICH-related
- stuff.
-
-
-
- Australian National University
- <http://cap.anu.edu.au/cap/projects/mpi/mpi.html>
- The Australian National University site contains information on
- the implementation of MPI on the Fujitsu AP1000 multicomputer
- located at the Australian National University as well as various
- links to other MPI information.
-
-
- Mississippi State University <http://www.erc.msstate.edu/mpi/>
- Contains pointers to MPI resources on the Web, pointers to
- implementations, pointers to tutorials, pointers to libraries,
- and other things. Home site of the MPI FAQ.
-
-
- MPI-2 Mailing List Archives <http://www.mpi-
- forum.org/archives/mail/mail.html>
- The MPI-Forum web page now contains the mail archive of the
- MPI-2 Forum mailing lists.
-
-
- Netlib <http://www.netlib.org/mpi/>
- Netlib has a fairly large repository of MPI information. It
- contains such items as the original MPI1 proposal and minutes
- from several of the MPI Forum meetings.
-
-
- Oak Ridge National Laboratory
- <http://www.epm.ornl.gov/~walker/mpi/>
- Oak Ridge maintains a well-organized resource center for MPI-
- related materials.
-
-
- Notre Dame LAM <http://www.mpi.nd.edu/lam>
- Notre Dame is now the home location for information about LAM,
- one of the public domain MPI implementations.
-
-
- MPI Validation Suite <http://www.ssd.intel.com/mpi.html>
- Intel's "MPI Validation Suite" is now available to the public.
- To download a copy, please visit the site above.
-
-
-
-
- 2.2. Newsgroup
-
-
- An MPI-specific newsgroup, comp.parallel.mpi was created by a vote of
- 506 to 14. The RFD for comp.parallel.mpi was originally posted to
- comp.parallel, comp.parallel.pvm, and news.announce.newgroups on April
- 4, 1994. The CFV was issued June 15, 1994. The voting results, RFD,
- and CFV can be retrieved by anonymous ftp from ftp.erc.msstate.edu as
- pub/mpi/newsgroup/result, pub/mpi/newsgroup/rfd and
- pub/mpi/newsgroup/cfv.
-
-
-
- 2.3. Implementations
-
-
- Many of the MPI WWW pages have information about the various MPI
- implementations. The Ohio Supercomputing Center is attempting to
- maintain a comprehensive list of implementations at
- <http://www.lsc.nd.edu/MPI/>. Information such as the supplier,
- current version, help contact, etc. can be found there.
-
- 3. MPI-2
-
-
-
- 3.1. MPI-2 Status
-
- It was decided at the final MPI-1 meeting (Feb. 1994) that plans for
- extending MPI should wait until people have had some experience with
- the current version of MPI. The MPI Forum held a BOF session at
- Supercomputing '94 to discuss the possibility of an MPI-2 effort. A
- decision was made to begin MPI-2 meetings in April of 1995. These
- meetings were held approximately every six weeks until October 11,
- 1997. After that meeting, the customary two month public comment
- period was initiated. At SuperComputing'96 (held in Pittsburgh, PA),
- the document was 'unveiled'. Meetings began again in January, 1997
- and continued approximately every six weeks until April 25, 1997. At
- this meeting, the MPI-2 Document was unanimously accepted by the
- voting institutions. The MPI-2 Document is viewable as HTML
- <http://www.mpi-forum.org/docs/mpi-20-html/mpi2-report.html> or
- downloadable as compressed postscript <http://www.mpi-
- forum.org/docs/mpi-20.ps.Z> or downloadable as uncompressed postscript
- <http://www.mpi-forum.org/docs/mpi-20.ps>.
-
-
-
- 3.2. What features are included in MPI-2?
-
-
- There are several major subsections of functionality addressed in the
- MPI-2 Standard.
-
- o Miscellaneous Topics
-
- o Dynamic Process Management
-
- o One-Sided Communication
-
- o Extended Collective Operations
-
- o External Interfaces
-
- o Parallel I/O
-
- o Language Bindings (C++ and Fortran-90)
-
- The I/O subcommittee was added after the MPI-2 process began. There
- were several other sections of the MPI-2 Document that were present
- during some form of the process that were removed from the document
- and placed in the Journal of Development (JOD). This document,
- which is also downloadable from the web site <http://www.mpi-
- forum.org/docs/mpi-20-jod.ps> was created so that ideas that were
- interesting but either were either of unknown value or weren't
- mature would not be lost and would be documented. One chapter on
- Real-Time MPI which was placed in the JOD but developed into a
- standards body of its own. This body has a web page located at
- <http://www.mpirt.org>.
-
-
-
- 3.3. What mailing lists were being used for MPI-2?
-
- If you wanted to participate in the discussion of a particular MPI-2
- topic, send mail to majordomo@mcs.anl.gov containing:
-
-
-
- subscribe <list-name> <your email address>
-
-
-
-
- The current mailing lists include:
-
-
- mpi-comm@mcs.anl.gov MPI Forum discussion list, all comments welcome
- mpi-core@mcs.anl.gov MPI forum meeting attendees list
-
- mpi-dynamic MPI Forum discussion list for dynamic process management
- mpi-1sided MPI Forum discussion list for one-sided communication
- mpi-coll MPI Forum discussion list for collective operations
- mpi-external MPI Forum discussion list for external interfaces
- mpi-bind MPI Forum discussion list for C++ and Fortran-90 bindings
- mpi-realtime MPI Forum discussion list for real-time extensions
- mpi-io MPI Forum discussion list for I/O
-
-
-
-
-
-
- 3.4. Where are the MPI-2 mailing lists archived?
-
- The MPI-2 mailing lists are archived using hypermail. These archived
- mailing lists can be retrieved from <http://www.mpi-
- forum.org/archives/mail/mail.html>.
-
-
-
- 3.5. Where is the current MPI-2 document?
-
- The MPI-2 Document can be viewed as HTML as <http://www.mpi-
- forum.org/docs/mpi-20-html/mpi2-report.html> or can be downloaded in
- compressed postscript form as <http://www.mpi-
- forum.org/docs/mpi-20.ps.Z> or as uncompressed postscript form as
- <http://www.mpi-forum.org/docs/mpi-20.ps>.
-
-
- 3.6. Where can I find out more about MPI-2?
-
-
- More information on MPI-2 is available from
- <http://www.erc.msstate.edu/mpi/mpi2.html> and <http://www.mpi-
- forum.org>. These sites contain information about minutes from MPI-2
- meetings, votes, etc.
-
-
-
- 3.7. What is MPI/RT?
-
-
- In the form of the MPI Forums, MPI/RT is a standards effort to design
- an MPI for Real-Time programming. This Forum meets approximately
- every six weeks to:
-
- o Create integrated messaging, scheduling, and parallel programming
- API together with syntax and semantics to support the emerging
- computational hierarchies of node architectures and gigabit/s
- networks efficiently.
-
- o Expand the horizons of performance-portable real-time programming
-
-
- o Support multiple real-time paradigms
-
- o Enhance the performance of Messaging over MPI-1 and MPI-2
-
- o Catalyze a new generation of portable parallel applications that
- require or benefit from the explicit use of time
-
-
- 3.8. Where can I find out more about MPI/RT?
-
- The MPI/RT Forum has a web site <http://www.mpirt.org>.
-
-
-
- 4. Administrative Information and Acknowledgments
-
-
-
- 4.1. Recent changes to the FAQ
-
-
- o Added references to MPI/RT.
-
- o Changed the content of the FAQ to reflect the current status of
- MPI.
-
- o Changed the format of the FAQ.
-
-
-
- 4.2. Formats in which this FAQ is Available
-
-
- This document is available as ASCII text, an Emacs Info document,
- PostScript, and HTML. It is also available on the world wide web
- (WWW) at <http://www.erc.msstate.edu/mpi/mpi-faq.html> or at
- <http://www.cis.ohio-state.edu/hypertext/faq/usenet/mpi-faq/faq.html>
-
- The text, Emacs Info, HTML, and Postscript versions are generated
- automatically by Linuxdoc-SGML, a text-formating package based on SGML
- used by Linux Documentation Project. Information on Linuxdoc-SGML can
- be found at <http://www.informatik.tu-muenchen.de/~schwarz/linuxdoc-
- sgml/>.
-
- The output files mpi-faq.txt, mpi-faq.info, mpi-faq.html, mpi-faq.ps,
- and mpi-faq.sgml are available at
- <ftp://ftp.erc.msstate.edu/pub/mpi/faq>. A tarfile (mpi-
- faq.source.tar.gz) also is available which contains all of these
- files.
-
-
-
- 4.3. Where can I get a copy of this FAQ?
-
-
- In addition to finding it in those places listed in question
- ``Formats'', the text version is posted monthly to comp.parallel.mpi,
- news.answers, and comp.answers.
-
- The text version is also available through anonymous ftp from
- <ftp://rtfm.mit.edu/pub/usenet/news.answers/mpi-faq> and
- <ftp://ftp.erc.msstate.edu/pub/mpi/faq/mpi-faq.txt> or those without
- FTP access can send e-mail to mail-server@rtfm.mit.edu with "send
- usenet/news.answers/mpi-faq" in the message body. You can also get a
- postscript verion from <ftp://ftp.erc.msstate.edu/pub/mpi/faq/mpi-
- faq.ps>
- 4.4. Disclaimer and Copyright
-
-
- Note that this document is provided as is. The information in it is
- not warranted to be correct; you use it at your own risk.
-
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