MPI: A Message-Passing Interface Standard Version 2.2

Message Passing Interface Forum

This document describes the Message-Passing Interface ( MPI) standard, version 2.2. The MPI standard includes point-to-point message-passing, collective communications, group and communicator concepts, process topologies, environmental management, process creation and management, one-sided communications, extended collective operations, external interfaces, I/O, some miscellaneous topics, and a profiling interface. Language bindings for C, C++ and Fortran are defined.

Technically, this version of the standard is based on `` MPI: A Message-Passing Interface Standard, version 2.1, June 23, 2008. The MPI Forum added seven new routines and a number of enhancements and clarifications to the standard.

Historically, the evolution of the standards is from MPI-1.0 (June 1994) to MPI-1.1 (June 12, 1995) to MPI-1.2 (July 18, 1997), with several clarifications and additions and published as part of the MPI-2 document, to MPI-2.0 (July 18, 1997), with new functionality, to MPI-1.3 (May 30, 2008), combining for historical reasons the documents 1.1 and 1.2 and some errata documents to one combined document, and to MPI-2.1 (June 23, 2008), combining the previous documents. This version, MPI-2.2, is based on MPI-2.1 and provides additional clarifications and errata corrections as well as a few enhancements.

(c) 1993, 1994, 1995, 1996, 1997, 2008, 2009 University of Tennessee, Knoxville, Tennessee. Permission to copy without fee all or part of this material is granted, provided the University of Tennessee copyright notice and the title of this document appear, and notice is given that copying is by permission of the University of Tennessee.

Version 2.2: September 4, 2009. This document contains mostly corrections and clarifications to the MPI 2.1 document. A few extensions have been added; however all correct MPI 2.1 programs are correct MPI 2.2 programs. New features were adopted only when there were compelling needs for users, open source implementations, and minor impact on existing MPI implementations.

Version 2.1: June 23, 2008. This document combines the previous documents MPI-1.3 (May 30, 2008) and MPI-2.0 (July 18, 1997). Certain parts of MPI-2.0, such as some sections of Chapter 4, Miscellany, and Chapter 7, Extended Collective Operations have been merged into the Chapters of MPI-1.3. Additional errata and clarifications collected by the MPI Forum are also included in this document.

Version 1.3: May 30, 2008. This document combines the previous documents MPI-1.1 (June 12, 1995) and the MPI-1.2 Chapter in MPI-2 (July 18, 1997). Additional errata collected by the MPI Forum referring to MPI-1.1 and MPI-1.2 are also included in this document.

Version 2.0: July 18, 1997. Beginning after the release of MPI-1.1, the MPI Forum began meeting to consider corrections and extensions. MPI-2 has been focused on process creation and management, one-sided communications, extended collective communications, external interfaces and parallel I/O. A miscellany chapter discusses items that don't fit elsewhere, in particular language interoperability.

Version 1.2: July 18, 1997. The MPI-2 Forum introduced MPI-1.2 as Chapter 3 in the standard " MPI-2: Extensions to the Message-Passing Interface", July 18, 1997. This section contains clarifications and minor corrections to Version 1.1 of the MPI Standard. The only new function in MPI-1.2 is one for identifying to which version of the MPI Standard the implementation conforms. There are small differences between MPI-1 and MPI-1.1. There are very few differences between MPI-1.1 and MPI-1.2, but large differences between MPI-1.2 and MPI-2.

Version 1.1: June, 1995. Beginning in March, 1995, the Message-Passing Interface Forum reconvened to correct errors and make clarifications in the MPI document of May 5, 1994, referred to below as Version 1.0. These discussions resulted in Version 1.1, which is this document. The changes from Version 1.0 are minor. A version of this document with all changes marked is available. This paragraph is an example of a change.

Version 1.0: May, 1994. The Message-Passing Interface Forum (MPIF), with participation from over 40 organizations, has been meeting since January 1993 to discuss and define a set of library interface standards for message passing. MPIF is not sanctioned or supported by any official standards organization.

The goal of the Message-Passing Interface, simply stated, is to develop a widely used standard for writing message-passing programs. As such the interface should establish a practical, portable, efficient, and flexible standard for message-passing.

This is the final report, Version 1.0, of the Message-Passing Interface Forum. This document contains all the technical features proposed for the interface. This copy of the draft was processed by LaTeX on May 5, 1994. Please send comments on MPI to mpi-comments@mpi-forum.org. Your comment will be forwarded to MPI Forum committee members who will attempt to respond.

Acknowledgments

This document represents the work of many people who have served on the MPI Forum. The meetings have been attended by dozens of people from many parts of the world. It is the hard and dedicated work of this group that has led to the MPI standard. The technical development was carried out by subgroups, whose work was reviewed by the full committee. During the period of development of the Message-Passing Interface ( MPI), many people helped with this effort. Those who served as primary coordinators in MPI-1.0 and MPI-1.1 are:


The following list includes some of the active participants in the MPI-1.0 and MPI-1.1 process not mentioned above.

Ed Anderson Robert Babb Joe Baron Eric Barszcz
Scott Berryman Rob Bjornson Nathan Doss Anne Elster
Jim Feeney Vince Fernando Sam Fineberg Jon Flower
Daniel Frye Ian Glendinning Adam Greenberg Robert Harrison
Leslie Hart Tom Haupt Don Heller Tom Henderson
Alex Ho C.T. Howard Ho Gary Howell John Kapenga
James Kohl Susan Krauss Bob Leary Arthur Maccabe
Peter Madams Alan Mainwaring Oliver McBryan Phil McKinley
Charles Mosher Dan Nessett Peter Pacheco Howard Palmer
Paul Pierce Sanjay Ranka Peter Rigsbee Arch Robison
Erich Schikuta Ambuj Singh Alan Sussman Robert Tomlinson
Robert G. Voigt Dennis Weeks Stephen Wheat Steve Zenith

The University of Tennessee and Oak Ridge National Laboratory made the draft available by anonymous FTP mail servers and were instrumental in distributing the document.

The work on the MPI-1 standard was supported in part by ARPA and NSF under grant ASC-9310330, the National Science Foundation Science and Technology Center Cooperative Agreement No. CCR-8809615, and by the Commission of the European Community through Esprit project P6643 (PPPE).


Contents

  • MPI-1.2 and MPI-2.0:
  • MPI-1.3 and MPI-2.1:
  • MPI-2.2:
  • Introduction to MPI
  • Overview and Goals
  • Background of MPI-1.0
  • Background of MPI-1.1, MPI-1.2, and MPI-2.0
  • Background of MPI-1.3 and MPI-2.1
  • Background of MPI-2.2
  • Who Should Use This Standard?
  • What Platforms Are Targets For Implementation?
  • What Is Included In The Standard?
  • What Is Not Included In The Standard?
  • Organization of this Document
  • MPI Terms and Conventions
  • Document Notation
  • Naming Conventions
  • Procedure Specification
  • Semantic Terms
  • Data Types
  • Opaque Objects
  • Array Arguments
  • State
  • Named Constants
  • Choice
  • Addresses
  • File Offsets
  • Language Binding
  • Deprecated Names and Functions
  • Fortran Binding Issues
  • C Binding Issues
  • C++ Binding Issues
  • Functions and Macros
  • Processes
  • Error Handling
  • Implementation Issues
  • Independence of Basic Runtime Routines
  • Interaction with Signals
  • Examples
  • Point-to-Point Communication
  • Introduction
  • Blocking Send and Receive Operations
  • Blocking Send
  • Message Data
  • Message Envelope
  • Blocking Receive
  • Return Status
  • Passing MPI_STATUS_IGNORE for Status
  • Data Type Matching and Data Conversion
  • Type Matching Rules
  • Type MPI_CHARACTER
  • Data Conversion
  • Communication Modes
  • Semantics of Point-to-Point Communication
  • Buffer Allocation and Usage
  • Model Implementation of Buffered Mode
  • Nonblocking Communication
  • Communication Request Objects
  • Communication Initiation
  • Communication Completion
  • Semantics of Nonblocking Communications
  • Multiple Completions
  • Non-destructive Test of status
  • Probe and Cancel
  • Persistent Communication Requests
  • Send-Receive
  • Null Processes
  • Datatypes
  • Derived Datatypes
  • Type Constructors with Explicit Addresses
  • Datatype Constructors
  • Subarray Datatype Constructor
  • Distributed Array Datatype Constructor
  • Address and Size Functions
  • Lower-Bound and Upper-Bound Markers
  • Extent and Bounds of Datatypes
  • True Extent of Datatypes
  • Commit and Free
  • Duplicating a Datatype
  • Use of General Datatypes in Communication
  • Correct Use of Addresses
  • Decoding a Datatype
  • Examples
  • Pack and Unpack
  • Canonical MPI_PACK and MPI_UNPACK
  • Collective Communication
  • Introduction and Overview
  • Communicator Argument
  • Specifics for Intracommunicator Collective Operations
  • Applying Collective Operations to Intercommunicators
  • Specifics for Intercommunicator Collective Operations
  • Barrier Synchronization
  • Broadcast
  • Example using MPI_BCAST
  • Gather
  • Examples using MPI_GATHER, MPI_GATHERV
  • Scatter
  • Examples using MPI_SCATTER, MPI_SCATTERV
  • Gather-to-all
  • Example using MPI_ALLGATHER
  • All-to-All Scatter/Gather
  • Global Reduction Operations
  • Reduce
  • Predefined Reduction Operations
  • Signed Characters and Reductions
  • MINLOC and MAXLOC
  • User-Defined Reduction Operations
  • Example of User-defined Reduce
  • All-Reduce
  • Process-local reduction
  • Reduce-Scatter
  • MPI_REDUCE_SCATTER_BLOCK
  • MPI_REDUCE_SCATTER
  • Scan
  • Inclusive Scan
  • Exclusive Scan
  • Example using MPI_SCAN
  • Correctness
  • Groups, Contexts, Communicators, and Caching
  • Introduction
  • Features Needed to Support Libraries
  • MPI's Support for Libraries
  • Basic Concepts
  • Groups
  • Contexts
  • Intra-Communicators
  • Predefined Intra-Communicators
  • Group Management
  • Group Accessors
  • Group Constructors
  • Group Destructors
  • Communicator Management
  • Communicator Accessors
  • Communicator Constructors
  • Communicator Destructors
  • Motivating Examples
  • Current Practice #1
  • Current Practice #2
  • (Approximate) Current Practice #3
  • Example #4
  • Library Example #1
  • Library Example #2
  • Inter-Communication
  • Inter-communicator Accessors
  • Inter-communicator Operations
  • Inter-Communication Examples
  • Example 1: Three-Group ``Pipeline"
  • Example 2: Three-Group ``Ring"
  • Caching
  • Functionality
  • Communicators
  • Windows
  • Datatypes
  • Error Class for Invalid Keyval
  • Attributes Example
  • Naming Objects
  • Formalizing the Loosely Synchronous Model
  • Basic Statements
  • Models of Execution
  • Static communicator allocation
  • Dynamic communicator allocation
  • The General case
  • Process Topologies
  • Introduction
  • Virtual Topologies
  • Embedding in MPI
  • Overview of the Functions
  • Topology Constructors
  • Cartesian Constructor
  • Cartesian Convenience Function: MPI_DIMS_CREATE
  • General (Graph) Constructor
  • Distributed (Graph) Constructor
  • Topology Inquiry Functions
  • Cartesian Shift Coordinates
  • Partitioning of Cartesian structures
  • Low-Level Topology Functions
  • An Application Example
  • MPI Environmental Management
  • Implementation Information
  • Version Inquiries
  • Environmental Inquiries
  • Tag Values
  • Host Rank
  • IO Rank
  • Clock Synchronization
  • Memory Allocation
  • Error Handling
  • Error Handlers for Communicators
  • Error Handlers for Windows
  • Error Handlers for Files
  • Freeing Errorhandlers and Retrieving Error Strings
  • Error Codes and Classes
  • Error Classes, Error Codes, and Error Handlers
  • Timers and Synchronization
  • Startup
  • Allowing User Functions at Process Termination
  • Determining Whether MPI Has Finished
  • Portable MPI Process Startup
  • The Info Object
  • Process Creation and Management
  • Introduction
  • The Dynamic Process Model
  • Starting Processes
  • The Runtime Environment
  • Process Manager Interface
  • Processes in MPI
  • Starting Processes and Establishing Communication
  • Starting Multiple Executables and Establishing Communication
  • Reserved Keys
  • Spawn Example
  • Manager-worker Example, Using MPI_COMM_SPAWN.
  • Establishing Communication
  • Names, Addresses, Ports, and All That
  • Server Routines
  • Client Routines
  • Name Publishing
  • Reserved Key Values
  • Client/Server Examples
  • Simplest Example --- Completely Portable.
  • Ocean/Atmosphere - Relies on Name Publishing
  • Simple Client-Server Example.
  • Other Functionality
  • Universe Size
  • Singleton MPI_INIT
  • MPI_APPNUM
  • Releasing Connections
  • Another Way to Establish MPI Communication
  • One-Sided Communications
  • Introduction
  • Initialization
  • Window Creation
  • Window Attributes
  • Communication Calls
  • Put
  • Get
  • Examples
  • Accumulate Functions
  • Synchronization Calls
  • Fence
  • General Active Target Synchronization
  • Lock
  • Assertions
  • Miscellaneous Clarifications
  • Examples
  • Error Handling
  • Error Handlers
  • Error Classes
  • Semantics and Correctness
  • Atomicity
  • Progress
  • Registers and Compiler Optimizations
  • External Interfaces
  • Introduction
  • Generalized Requests
  • Examples
  • Associating Information with Status
  • MPI and Threads
  • General
  • Clarifications
  • Initialization
  • I/O
  • Introduction
  • Definitions
  • File Manipulation
  • Opening a File
  • Closing a File
  • Deleting a File
  • Resizing a File
  • Preallocating Space for a File
  • Querying the Size of a File
  • Querying File Parameters
  • File Info
  • Reserved File Hints
  • File Views
  • Data Access
  • Data Access Routines
  • Positioning
  • Synchronism
  • Coordination
  • Data Access Conventions
  • Data Access with Explicit Offsets
  • Data Access with Individual File Pointers
  • Data Access with Shared File Pointers
  • Noncollective Operations
  • Collective Operations
  • Seek
  • Split Collective Data Access Routines
  • File Interoperability
  • Datatypes for File Interoperability
  • External Data Representation: ``external32''
  • User-Defined Data Representations
  • Extent Callback
  • Datarep Conversion Functions
  • Matching Data Representations
  • Consistency and Semantics
  • File Consistency
  • Random Access vs. Sequential Files
  • Progress
  • Collective File Operations
  • Type Matching
  • Miscellaneous Clarifications
  • MPI_Offset Type
  • Logical vs. Physical File Layout
  • File Size
  • Examples
  • Asynchronous I/O
  • I/O Error Handling
  • I/O Error Classes
  • Examples
  • Double Buffering with Split Collective I/O
  • Subarray Filetype Constructor
  • Profiling Interface
  • Requirements
  • Discussion
  • Logic of the Design
  • Miscellaneous Control of Profiling
  • Examples
  • Profiler Implementation
  • MPI Library Implementation
  • Systems with Weak Symbols
  • Systems Without Weak Symbols
  • Complications
  • Multiple Counting
  • Linker Oddities
  • Multiple Levels of Interception
  • Deprecated Functions
  • Deprecated since MPI-2.0
  • Deprecated since MPI-2.2
  • Language Bindings
  • C++
  • Overview
  • Design
  • C++ Classes for MPI
  • Class Member Functions for MPI
  • Semantics
  • C++ Datatypes
  • Communicators
  • Exceptions
  • Mixed-Language Operability
  • Profiling
  • Fortran Support
  • Overview
  • Problems With Fortran Bindings for MPI
  • Problems Due to Strong Typing
  • Problems Due to Data Copying and Sequence Association
  • Special Constants
  • Fortran 90 Derived Types
  • A Problem with Register Optimization
  • Basic Fortran Support
  • Extended Fortran Support
  • The mpi Module
  • No Type Mismatch Problems for Subroutines with Choice Arguments
  • Additional Support for Fortran Numeric Intrinsic Types
  • Parameterized Datatypes with Specified Precision and Exponent Range
  • Support for Size-specific MPI Datatypes
  • Communication With Size-specific Types
  • Language Interoperability
  • Introduction
  • Assumptions
  • Initialization
  • Transfer of Handles
  • Status
  • MPI Opaque Objects
  • Datatypes
  • Callback Functions
  • Error Handlers
  • Reduce Operations
  • Addresses
  • Attributes
  • Extra State
  • Constants
  • Interlanguage Communication
  • Language Bindings Summary
  • Defined Values and Handles
  • Defined Constants
  • Types
  • Prototype definitions
  • Deprecated prototype definitions
  • Info Keys
  • Info Values
  • C Bindings
  • Point-to-Point Communication C Bindings
  • Datatypes C Bindings
  • Collective Communication C Bindings
  • Groups, Contexts, Communicators, and Caching C Bindings
  • Process Topologies C Bindings
  • MPI Environmenta Management C Bindings
  • The Info Object C Bindings
  • Process Creation and Management C Bindings
  • One-Sided Communications C Bindings
  • External Interfaces C Bindings
  • I/O C Bindings
  • Language Bindings C Bindings
  • Profiling Interface C Bindings
  • Deprecated C Bindings
  • Fortran Bindings
  • Point-to-Point Communication Fortran Bindings
  • Datatypes Fortran Bindings
  • Collective Communication Fortran Bindings
  • Groups, Contexts, Communicators, and Caching Fortran Bindings
  • Process Topologies Fortran Bindings
  • MPI Environmenta Management Fortran Bindings
  • The Info Object Fortran Bindings
  • Process Creation and Management Fortran Bindings
  • One-Sided Communications Fortran Bindings
  • External Interfaces Fortran Bindings
  • I/O Fortran Bindings
  • Language Bindings Fortran Bindings
  • Profiling Interface Fortran Bindings
  • Deprecated Fortran Bindings
  • C++ Bindings (deprecated)
  • Point-to-Point Communication C++ Bindings
  • Datatypes C++ Bindings
  • Collective Communication C++ Bindings
  • Groups, Contexts, Communicators, and Caching C++ Bindings
  • Process Topologies C++ Bindings
  • MPI Environmenta Management C++ Bindings
  • The Info Object C++ Bindings
  • Process Creation and Management C++ Bindings
  • One-Sided Communications C++ Bindings
  • External Interfaces C++ Bindings
  • I/O C++ Bindings
  • Language Bindings C++ Bindings
  • Profiling Interface C++ Bindings
  • C++ Bindings on all MPI Classes
  • Construction / Destruction
  • Copy / Assignment
  • Comparison
  • Inter-language Operability
  • Change-Log
  • Changes from Version 2.1 to Version 2.2
  • Changes from Version 2.0 to Version 2.1
  • Bibliography
  • Index
  • Index
  • Index
  • Index
  • Index


  • Return to MPI-2.2 Standard Index
    Return to MPI Forum Home Page

    (Unofficial) MPI-2.2 of September 4, 2009
    HTML Generated on September 10, 2009