             Open Fabrics Enterprise Distribution (OFED)
     Open MPI in OFED 1.4.1 Copyrights, License, and Release Notes
			  
                             May 2009

Open MPI Copyrights
-------------------
Most files in this release are marked with the copyrights of the
organizations who have edited them.  The copyrights below generally
reflect members of the Open MPI core team who have contributed code to
this release.  The copyrights for code used under license from other
parties are included in the corresponding files.

Copyright (c) 2004-2008 The Trustees of Indiana University and Indiana
                        University Research and Technology
                        Corporation.  All rights reserved.
Copyright (c) 2004-2009 The University of Tennessee and The University
                        of Tennessee Research Foundation.  All rights
                        reserved.
Copyright (c) 2004-2008 High Performance Computing Center Stuttgart, 
                        University of Stuttgart.  All rights reserved.
Copyright (c) 2004-2007 The Regents of the University of California.
                        All rights reserved.
Copyright (c) 2006-2009 Los Alamos National Security, LLC.  All rights
                        reserved. 
Copyright (c) 2006-2009 Cisco Systems, Inc.  All rights reserved.
Copyright (c) 2006-2008 Voltaire, Inc. All rights reserved.
Copyright (c) 2006-2008 Sandia National Laboratories. All rights reserved.
Copyright (c) 2006-2009 Sun Microsystems, Inc.  All rights reserved.
                        Use is subject to license terms.
Copyright (c) 2006-2009 The University of Houston. All rights reserved.
Copyright (c) 2006-2008 Myricom, Inc.  All rights reserved.
Copyright (c) 2007-2008 UT-Battelle, LLC. All rights reserved.
Copyright (c) 2007-2008 IBM Corporation.  All rights reserved.
Copyright (c) 1998-2005 Forschungszentrum Juelich, Juelich Supercomputing 
                        Centre, Federal Republic of Germany
Copyright (c) 2005-2008 ZIH, TU Dresden, Federal Republic of Germany
Copyright (c) 2007      Evergrid, Inc. All rights reserved.
Copyright (c) 2008      Institut National de Recherche en
                        Informatique.  All rights reserved.
Copyright (c) 2007      Lawrence Livermore National Security, LLC.
                        All rights reserved.
Copyright (c) 2007-2009 Mellanox Technologies.  All rights reserved.
Copyright (c) 2006      QLogic Corporation.  All rights reserved.

Additional copyrights may follow

Open MPI License
----------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

- Redistributions of source code must retain the above copyright
  notice, this list of conditions and the following disclaimer.

- Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer listed
  in this license in the documentation and/or other materials
  provided with the distribution.

- Neither the name of the copyright holders nor the names of its
  contributors may be used to endorse or promote products derived from
  this software without specific prior written permission.

The copyright holders provide no reassurances that the source code
provided does not infringe any patent, copyright, or any other
intellectual property rights of third parties.  The copyright holders
disclaim any liability to any recipient for claims brought against
recipient by any third party for infringement of that parties
intellectual property rights.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

===========================================================================

When submitting questions and problems, be sure to include as much
extra information as possible.  This web page details all the
information that we request in order to provide assistance:

     http://www.open-mpi.org/community/help/

The best way to report bugs, send comments, or ask questions is to
sign up on the user's and/or developer's mailing list (for user-level
and developer-level questions; when in doubt, send to the user's
list):

        users@open-mpi.org
        devel@open-mpi.org

Because of spam, only subscribers are allowed to post to these lists
(ensure that you subscribe with and post from exactly the same e-mail
address -- joe@example.com is considered different than
joe@mycomputer.example.com!).  Visit these pages to subscribe to the
lists:

     http://www.open-mpi.org/mailman/listinfo.cgi/users
     http://www.open-mpi.org/mailman/listinfo.cgi/devel

Thanks for your time.

===========================================================================

Much, much more information is also available in the Open MPI FAQ:

    http://www.open-mpi.org/faq/

===========================================================================

OFED-Specific Release Notes
---------------------------

** SLES 10 with Pathscale compiler support:

Using the Pathscale compiler to build Open MPI on SLES10 may result in
a non-functional Open MPI installation (every Open MPI command fails).
If this problem occurs, try upgrading your Pathscale installation to
the latest maintenance release, or use a different compiler to compile
Open MPI.

** Intel compiler support:

Some versions of the Intel 9.1 C++ compiler suite series produce
incorrect code when used with the Open MPI C++ bindings.  Symptoms of
this problem include crashing applications (e.g., segmentation
violations) and Open MPI producing errors about incorrect parameters.
Be sure to upgrade to the latest maintenance release of the Intel 9.1
compiler to avoid these problems.

** Installing newer versions of Open MPI after OFED is installed:

Open MPI can be built from source after OFED is fully installed.  The
source code for Open MPI can be extracted from the SRPM shipped with
OFED or downloaded from the main Open MPI web site:
http://www.open-mpi.org/.

To compile with Open MPI from source with OFED support, fully install
the rest of OFED.  If you used the default prefix for the OFED
installation (/usr), Open MPI should build with OpenFabrics support by
default.  If you used a different OFED prefix, you must tell Open MPI
what it is with the "--with-openib=<OFED_prefix>" switch to configure.
You can verify that Open MPI installed with OpenFabrics support by
running (the exact version numbers displayed may be different; the
important part is that the "openib" BTL is displayed):

  shell$ ompi_info | grep openib
          MCA btl: openib (MCA v2.0, API v2.0, Component v1.3.2)

See the rest of the documentation below for other configure command
line options and installation instructions.

** Changelog summary

Showing versions 1.2.7 - 1.3.2; see the "NEWS" file in an Open MPI
distribution for the full list.

1.3.2
-----

- Fixed a potential infinite loop in the openib BTL that could occur
  in senders in some frequent-communication scenarios.  Thanks to Don
  Wood for reporting the problem.
- Add a new checksum PML variation on ob1 (main MPI point-to-point
  communication engine) to detect memory corruption in node-to-node
  messages
- Add a new configuration option to add padding to the openib
  header so the data is aligned
- Add a new configuration option to use an alternative checksum algo
  when using the checksum PML
- Fixed a problem reported by multiple users on the mailing list that
  the LSF support would fail to find the appropriate libraries at
  run-time.
- Allow empty shell designations from getpwuid().  Thanks to Sergey
  Koposov for the bug report.
- Ensure that mpirun exits with non-zero status when applications die
  due to user signal.  Thanks to Geoffroy Pignot for suggesting the
  fix.
- Ensure that MPI_VERSION / MPI_SUBVERSION match what is returned by
  MPI_GET_VERSION.  Thanks to Rob Egan for reporting the error.
- Updated MPI_*KEYVAL_CREATE functions to properly handle Fortran
  extra state.
- A variety of ob1 (main MPI point-to-point communication engine) bug
  fixes that could have caused hangs or seg faults.
- Do not install Open MPI's signal handlers in MPI_INIT if there are
  already signal handlers installed.  Thanks to Kees Verstoep for
  bringing the issue to our attention.
- Fix GM support to not seg fault in MPI_INIT.
- Various VampirTrace fixes.
- Various PLPA fixes.
- No longer create BTLs for invalid (TCP) devices.
- Various man page style and lint cleanups.
- Fix critical OpenFabrics-related bug noted here:
  http://www.open-mpi.org/community/lists/announce/2009/03/0029.php.
  Open MPI now uses a much more robust memory intercept scheme that is
  quite similar to what is used by MX.  The use of "-lopenmpi-malloc"
  is no longer necessary, is deprecated, and is expected to disappear
  in a future release.  -lopenmpi-malloc will continue to work for the
  duration of the Open MPI v1.3 and v1.4 series.
- Fix some OpenFabrics shutdown errors, both regarding iWARP and SRQ.
- Allow the udapl BTL to work on Solaris platforms that support
  relaxed PCI ordering.
- Fix problem where the mpirun would sometimes use rsh/ssh to launch on
  the localhost (instead of simply forking).
- Minor SLURM stdin fixes.
- Fix to run properly under SGE jobs.
- Scalability and latency improvements for shared memory jobs: convert
  to using one message queue instead of N queues.
- Automatically size the shared-memory area (mmap file) to match
  better what is needed;  specifically, so that large-np jobs will start.
- Use fixed-length MPI predefined handles in order to provide ABI
  compatibility between Open MPI releases.
- Fix building of the posix paffinity component to properly get the
  number of processors in loosely tested environments (e.g.,
  FreeBSD).  Thanks to Steve Kargl for reporting the issue.
- Fix --with-libnuma handling in configure.  Thanks to Gus Correa for
  reporting the problem.


1.3.1
-----

- Added "sync" coll component to allow users to synchronize every N
  collective operations on a given communicator.
- Increased the default values of the IB and RNR timeout MCA parameters.
- Fix a compiler error noted by Mostyn Lewis with the PGI 8.0 compiler.
- Fix an error that prevented stdin from being forwarded if the
  rsh launcher was in use.  Thanks to Branden Moore for pointing out
  the problem.
- Correct a case where the added datatype is considered as contiguous but
  has gaps in the beginning.
- Fix an error that limited the number of comm_spawns that could
  simultaneously be running in some environments
- Correct a corner case in OB1's GET protocol for long messages; the
  error could sometimes cause MPI jobs using the openib BTL to hang.
- Fix a bunch of bugs in the IO forwarding (IOF) subsystem and add some
  new options to output to files and redirect output to xterm.  Thanks to
  Jody Weissmann for helping test out many of the new fixes and
  features.
- Fix SLURM race condition.
- Fix MPI_File_c2f(MPI_FILE_NULL) to return 0, not -1.  Thanks to
  Lisandro Dalcin for the bug report.
- Fix the DSO build of tm PLM.
- Various fixes for size disparity between C int's and Fortran
  INTEGER's.  Thanks to Christoph van Wullen for the bug report.
- Ensure that mpirun exits with a non-zero exit status when daemons or
  processes abort or fail to launch.
- Various fixes to work around Intel (NetEffect) RNIC behavior.
- Various fixes for mpirun's --preload-files and --preload-binary
  options.
- Fix the string name in MPI::ERRORS_THROW_EXCEPTIONS.
- Add ability to forward SIFTSTP and SIGCONT to MPI processes if you
  set the MCA parameter orte_forward_job_control to 1.
- Allow the sm BTL to allocate larger amounts of shared memory if
  desired (helpful for very large multi-core boxen).
- Fix a few places where we used PATH_MAX instead of OMPI_PATH_MAX,
  leading to compile problems on some platforms.  Thanks to Andrea Iob
  for the bug report.
- Fix mca_btl_openib_warn_no_device_params_found MCA parameter; it
  was accidentally being ignored.
- Fix some run-time issues with the sctp BTL.
- Ensure that RTLD_NEXT exists before trying to use it (e.g., it
  doesn't exist on Cygwin).  Thanks to Gustavo Seabra for reporting
  the issue.
- Various fixes to VampirTrace, including fixing compile errors on
  some platforms.
- Fixed missing MPI_Comm_accept.3 man page; fixed minor issue in
  orterun.1 man page.  Thanks to Dirk Eddelbuettel for identifying the
  problem and submitting a patch.
- Implement the XML formatted output of stdout/stderr/stddiag.
- Fixed mpirun's -wdir switch to ensure that working directories for
  multiple app contexts are properly handled.  Thanks to Geoffroy
  Pignot for reporting the problem.
- Improvements to the MPI C++ integer constants:
  - Allow MPI::SEEK_* constants to be used as constants
  - Allow other MPI C++ constants to be used as array sizes
- Fix minor problem with orte-restart's command line options.  See
  ticket #1761 for details.  Thanks to Gregor Dschung for reporting
  the problem.

1.3
---

- Extended the OS X 10.5.x (Leopard) workaround for a problem when
  assembly code is compiled with -g[0-9].  Thanks to Barry Smith for
  reporting the problem.  See ticket #1701.
- Disabled MPI_REAL16 and MPI_COMPLEX32 support on platforms where the
  bit representation of REAL*16 is different than that of the C type
  of the same size (usually long double).  Thanks to Julien Devriendt
  for reporting the issue.  See ticket #1603.
- Increased the size of MPI_MAX_PORT_NAME to 1024 from 36. See ticket #1533.
- Added "notify debugger on abort" feature. See tickets #1509 and #1510.
  Thanks to Seppo Sahrakropi for the bug report.
- Upgraded Open MPI tarballs to use Autoconf 2.63, Automake 1.10.1,
  Libtool 2.2.6a.
- Added missing MPI::Comm::Call_errhandler() function.  Thanks to Dave
  Goodell for bringing this to our attention.
- Increased MPI_SUBVERSION value in mpi.h to 1 (i.e., MPI 2.1).
- Changed behavior of MPI_GRAPH_CREATE, MPI_TOPO_CREATE, and several
  other topology functions per MPI-2.1.
- Fix the type of the C++ constant MPI::IN_PLACE.
- Various enhancements to the openib BTL:
  - Added btl_openib_if_[in|ex]clude MCA parameters for
    including/excluding comma-delimited lists of HCAs and ports.
  - Added RDMA CM support, includng btl_openib_cpc_[in|ex]clude MCA
    parameters
  - Added NUMA support to only use "near" network adapters
  - Added "Bucket SRQ" (BSRQ) support to better utilize registered
    memory, including btl_openib_receive_queues MCA parameter
  - Added ConnectX XRC support (and integrated with BSRQ)
  - Added btl_openib_ib_max_inline_data MCA parameter
  - Added iWARP support
  - Revamped flow control mechansisms to be more efficient
  - "mpi_leave_pinned=1" is now the default when possible,
    automatically improving performance for large messages when
    application buffers are re-used
- Elimiated duplicated error messages when multiple MPI processes fail
  with the same error.
- Added NUMA support to the shared memory BTL.
- Add Valgrind-based memory checking for MPI-semantic checks.
- Add support for some optional Fortran datatypes (MPI_LOGICAL1,
  MPI_LOGICAL2, MPI_LOGICAL4 and MPI_LOGICAL8).
- Remove the use of the STL from the C++ bindings.
- Added support for Platform/LSF job launchers.  Must be Platform LSF
  v7.0.2 or later.
- Updated ROMIO with the version from MPICH2 1.0.7.
- Added RDMA capable one-sided component (called rdma), which
  can be used with BTL components that expose a full one-sided
  interface.
- Added the optional datatype MPI_REAL2. As this is added to the "end of"
  predefined datatypes in the fortran header files, there will not be
  any compatibility issues.
- Added Portable Linux Processor Affinity (PLPA) for Linux.
- Addition of a finer symbols export control via the visibiliy feature
  offered by some compilers.
- Added checkpoint/restart process fault tolerance support. Initially
  support a LAM/MPI-like protocol.
- Removed "mvapi" BTL; all InfiniBand support now uses the OpenFabrics
  driver stacks ("openib" BTL).
- Added more stringent MPI API parameter checking to help user-level
  debugging.
- The ptmalloc2 memory manager component is now by default built as
  a standalone library named libopenmpi-malloc.  Users wanting to
  use leave_pinned with ptmalloc2 will now need to link the library
  into their application explicitly.  All other users will use the
  libc-provided allocator instead of Open MPI's ptmalloc2.  This change
  may be overriden with the configure option enable-ptmalloc2-internal
- The leave_pinned options will now default to using mallopt on
  Linux in the cases where ptmalloc2 was not linked in.  mallopt
  will also only be available if munmap can be intercepted (the
  default whenever Open MPI is not compiled with --without-memory-
  manager.
- Open MPI will now complain and refuse to use leave_pinned if
  no memory intercept / mallopt option is available.
- Add option of using Perl-based wrapper compilers instead of the
  C-based wrapper compilers.  The Perl-based version does not
  have the features of the C-based version, but does work better
  in cross-compile environments.


1.2.9
-----

- Fix a segfault when using one-sided communications on some forms of derived
  datatypes.  Thanks to Dorian Krause for reporting the bug. See #1715.
- Fix an alignment problem affecting one-sided communications on
  some architectures (e.g., SPARC64). See #1738.
- Fix compilation on Solaris when thread support is enabled in Open MPI
  (e.g., when using --with-threads). See #1736.
- Correctly take into account the MTU that an OpenFabrics device port
  is using. See #1722 and
  https://bugs.openfabrics.org/show_bug.cgi?id=1369.
- Fix two datatype engine bugs. See #1677.
  Thanks to Peter Kjellstrom for the bugreport.
- Fix the bml r2 help filename so the help message can be found. See #1623.
- Fix a compilation problem on RHEL4U3 with the PGI 32 bit compiler
  caused by <infiniband/driver.h>.  See ticket #1613.
- Fix the --enable-cxx-exceptions configure option. See ticket #1607.
- Properly handle when the MX BTL cannot open an endpoint. See ticket #1621.
- Fix a double free of events on the tcp_events list. See ticket #1631.
- Fix a buffer overun in opal_free_list_grow (called by MPI_Init).
  Thanks to Patrick Farrell for the bugreport and Stephan Kramer for
  the bugfix.  See ticket #1583.
- Fix a problem setting OPAL_PREFIX for remote sh-based shells.
  See ticket #1580.


1.2.8
-----

- Tweaked one memory barrier in the openib component to be more conservative.
  May fix a problem observed on PPC machines.  See ticket #1532.
- Fix OpenFabrics IB partition support. See ticket #1557.
- Restore v1.1 feature that sourced .profile on remote nodes if the default
  shell will not do so (e.g. /bin/sh and /bin/ksh).  See ticket #1560.
- Fix segfault in MPI_Init_thread() if ompi_mpi_init() fails. See ticket #1562.
- Adjust SLURM support to first look for $SLURM_JOB_CPUS_PER_NODE instead of
  the deprecated $SLURM_TASKS_PER_NODE environment variable.  This change
  may be *required* when using SLURM v1.2 and above.  See ticket #1536.
- Fix the MPIR_Proctable to be in process rank order. See ticket #1529.
- Fix a regression introduced in 1.2.6 for the IBM eHCA. See ticket #1526.


1.2.7
-----

- Add some Sun HCA vendor IDs.  See ticket #1461.
- Fixed a memory leak in MPI_Alltoallw when called from Fortran.
  Thanks to Dave Grote for the bugreport.  See ticket #1457.
- Only link in libutil when it is needed/desired.  Thanks to
  Brian Barret for diagnosing and fixing the problem.  See ticket #1455.
- Update some QLogic HCA vendor IDs.  See ticket #1453.
- Fix F90 binding for MPI_CART_GET.  Thanks to Scott Beardsley for
  bringing it to our attention. See ticket #1429.
- Remove a spurious warning message generated in/by ROMIO. See ticket #1421.
- Fix a bug where command-line MCA parameters were not overriding
  MCA parameters set from environment variables.  See ticket #1380.
- Fix a bug in the AMD64 atomics assembly.  Thanks to Gabriele Fatigati
  for the bug report and bugfix.  See ticket #1351.
- Fix a gather and scatter bug on intercommunicators when the datatype
  being moved is 0 bytes. See ticket #1331.
- Some more man page fixes from the Debian maintainers.
  See tickets #1324 and #1329.
- Have openib BTL (OpenFabrics support) check for the presence of
  /sys/class/infiniband before allowing itself to be used.  This check
  prevents spurious "OMPI did not find RDMA hardware!" notices on
  systems that have the software drivers installed, but no
  corresponding hardware.  See tickets #1321 and #1305.
- Added vendor IDs for some ConnectX openib HCAs. See ticket #1311.
- Fix some RPM specfile inconsistencies.  See ticket #1308.
  Thanks to Jim Kusznir for noticing the problem.
- Removed an unused function prototype that caused warnings on
  some systems (e.g., OS X).  See ticket #1274.
- Fix a deadlock in inter-communicator scatter/gather operations.
  Thanks to Martin Audet for the bug report.  See ticket #1268.

===========================================================================

Much, much more information is also available in the Open MPI FAQ:

    http://www.open-mpi.org/faq/

===========================================================================

General Release Notes
---------------------

Detailed Open MPI v1.3 Feature List:

  o Open MPI RunTime Environment (ORTE) improvements
    - General robustness improvements
    - Scalable job launch (we've seen ~16K processes in less than a
      minute in a highly-optimized configuration)
    - New process mappers
    - Support for Platform/LSF environments (v7.0.2 and later)
    - More flexible processing of host lists
    - new mpirun cmd line options and associated functionality

  o Fault-Tolerance Features
    - Asynchronous, transparent checkpoint/restart support
      - Fully coordinated checkpoint/restart coordination component
      - Support for the following checkpoint/restart services:
        - blcr: Berkley Lab's Checkpoint/Restart
        - self: Application level callbacks
      - Support for the following interconnects:
        - tcp
        - mx
        - openib 
        - sm
        - self
    - Improved Message Logging

  o MPI_THREAD_MULTIPLE support for point-to-point messaging in the
    following BTLs (note that only MPI point-to-point messaging API
    functions support MPI_THREAD_MULTIPLE; other API functions likely
    do not):
    - tcp
    - sm
    - mx
    - elan
    - self

  o Point-to-point Messaging Layer (PML) improvements
    - Memory footprint reduction
    - Improved latency
    - Improved algorithm for multiple communication device
      ("multi-rail") support

  o Numerous Open Fabrics improvements/enhancements
    - Added iWARP support (including RDMA CM)
    - Memory footprint and performance improvements
      - "Bucket" SRQ support for better registered memory utilization
      - XRC/ConnectX support
      - Message coalescing
    - Improved error report mechanism with Asynchronous events
    - Automatic Path Migration (APM)
    - Improved processor/port binding
    - Infrastructure for additional wireup strategies
    - mpi_leave_pinned is now enabled by default

  o uDAPL BTL enhancements
    - Multi-rail support
    - Subnet checking
    - Interface include/exclude capabilities

  o  Processor affinity
    - Linux processor affinity improvements
    - Core/socket <--> process mappings

  o Collectives
    - Performance improvements
    - Support for hierarchical collectives (must be activated
      manually; see below)

  o Miscellaneous
    - MPI 2.1 compliant 
    - Sparse process groups and communicators
    - Support for Cray Compute Node Linux (CNL)
    - One-sided RDMA component (BTL-level based rather than PML-level
      based)
    - Aggregate MCA parameter sets
    - MPI handle debugging
    - Many small improvements to the MPI C++ bindings
    - Valgrind support
    - VampirTrace support
    - Updated ROMIO to the version from MPICH2 1.0.7
    - Removed the mVAPI IB stacks
    - Display most error messages only once (vs. once for each
      process)
    - Many other small improvements and bug fixes, too numerous to
      list here

Known issues
------------

  o There is a segfault that sometimes occurs on one of our x86_64 test
    clusters when using MPI onesided communications over Myrinet MX.
    Since no one else has reported this problem we are not holding
    up the 1.3 release.  See ticket #1757 for the details, and any
    possible workarounds.

  o XGrid support is currently broken.
    https://svn.open-mpi.org/trac/ompi/ticket/1777

  o MPI_REDUCE_SCATTER does not work with counts of 0.
    https://svn.open-mpi.org/trac/ompi/ticket/1559

  o Please also see the Open MPI bug tracker for bugs beyond this release.
    https://svn.open-mpi.org/trac/ompi/report

===========================================================================

The following abbreviated list of release notes applies to this code
base as of this writing (14 April 2009):

General notes
-------------

- Open MPI includes support for a wide variety of supplemental
  hardware and software package.  When configuring Open MPI, you may
  need to supply additional flags to the "configure" script in order
  to tell Open MPI where the header files, libraries, and any other
  required files are located.  As such, running "configure" by itself
  may not include support for all the devices (etc.) that you expect,
  especially if their support headers / libraries are installed in
  non-standard locations.  Network interconnects are an easy example
  to discuss -- Myrinet and OpenFabrics networks, for example, both
  have supplemental headers and libraries that must be found before
  Open MPI can build support for them.  You must specify where these
  files are with the appropriate options to configure.  See the
  listing of configure command-line switches, below, for more details.

- The majority of Open MPI's documentation is here in this file, the
  included man pages, and on the web site FAQ
  (http://www.open-mpi.org/).  This will eventually be supplemented
  with cohesive installation and user documentation files.

- Note that Open MPI documentation uses the word "component"
  frequently; the word "plugin" is probably more familiar to most
  users.  As such, end users can probably completely substitute the
  word "plugin" wherever you see "component" in our documentation.
  For what it's worth, we use the word "component" for historical
  reasons, mainly because it is part of our acronyms and internal API
  functionc calls.

- The run-time systems that are currently supported are:
  - rsh / ssh
  - LoadLeveler
  - PBS Pro, Open PBS, Torque
  - Platform LSF (v7.0.2 and later)
  - SLURM
  - XGrid (known to be broken in 1.3 through 1.3.2)
  - Cray XT-3 and XT-4
  - Sun Grid Engine (SGE) 6.1, 6.2 and open source Grid Engine
  - Microsoft Windows CCP (Microsoft Windows server 2003 and 2008)

- Systems that have been tested are:
  - Linux (various flavors/distros), 32 bit, with gcc, and Sun Studio 12
  - Linux (various flavors/distros), 64 bit (x86), with gcc, Absoft,
    Intel, Portland, Pathscale, and Sun Studio 12 compilers (*)
  - OS X (10.4), 32 and 64 bit (i386, PPC, PPC64, x86_64), with gcc
    and Absoft compilers (*)
  - Solaris 10 update 2, 3 and 4, 32 and 64 bit (SPARC, i386, x86_64),
    with Sun Studio 10, 11 and 12

  (*) Be sure to read the Compiler Notes, below.

- Other systems have been lightly (but not fully tested):
  - Other 64 bit platforms (e.g., Linux on PPC64)
  - Microsoft Windows CCP (Microsoft Windows server 2003 and 2008);
    more testing and support is expected later in the Open MPI v1.3.x
    series.

Compiler Notes
--------------

- Mixing compilers from different vendors when building Open MPI
  (e.g., using the C/C++ compiler from one vendor and the F77/F90
  compiler from a different vendor) has been successfully employed by
  some Open MPI users (discussed on the Open MPI user's mailing list),
  but such configurations are not tested and not documented.  For
  example, such configurations may require additional compiler /
  linker flags to make Open MPI build properly.

- Open MPI does not support the Sparc v8 CPU target, which is the
  default on Sun Solaris.  The v8plus (32 bit) or v9 (64 bit)
  targets must be used to build Open MPI on Solaris.  This can be
  done by including a flag in CFLAGS, CXXFLAGS, FFLAGS, and FCFLAGS,
  -xarch=v8plus for the Sun compilers, -mv8plus for GCC.

- At least some versions of the Intel 8.1 compiler seg fault while
  compiling certain Open MPI source code files.  As such, it is not
  supported.

- The Intel 9.0 v20051201 compiler on IA64 platforms seems to have a
  problem with optimizing the ptmalloc2 memory manager component (the
  generated code will segv).  As such, the ptmalloc2 component will
  automatically disable itself if it detects that it is on this
  platform/compiler combination.  The only effect that this should
  have is that the MCA parameter mpi_leave_pinned will be inoperative.

- Early versions of the Portland Group 6.0 compiler have problems
  creating the C++ MPI bindings as a shared library (e.g., v6.0-1).
  Tests with later versions show that this has been fixed (e.g.,
  v6.0-5).

- The Portland Group compilers prior to version 7.0 require the
  "-Msignextend" compiler flag to extend the sign bit when converting
  from a shorter to longer integer.  This is is different than other
  compilers (such as GNU).  When compiling Open MPI with the Portland
  compiler suite, the following flags should be passed to Open MPI's
  configure script:

  shell$ ./configure CFLAGS=-Msignextend CXXFLAGS=-Msignextend \
	--with-wrapper-cflags=-Msignextend \
	--with-wrapper-cxxflags=-Msignextend ...

  This will both compile Open MPI with the proper compile flags and
  also automatically add "-Msignextend" when the C and C++ MPI wrapper
  compilers are used to compile user MPI applications.

- Using the MPI C++ bindings with the Pathscale compiler is known
  to fail, possibly due to Pathscale compiler issues.

- Using the Absoft compiler to build the MPI Fortran bindings on Suse
  9.3 is known to fail due to a Libtool compatibility issue.

- Open MPI will build bindings suitable for all common forms of
  Fortran 77 compiler symbol mangling on platforms that support it
  (e.g., Linux).  On platforms that do not support weak symbols (e.g.,
  OS X), Open MPI will build Fortran 77 bindings just for the compiler
  that Open MPI was configured with.  

  Hence, on platforms that support it, if you configure Open MPI with
  a Fortran 77 compiler that uses one symbol mangling scheme, you can
  successfully compile and link MPI Fortran 77 applications with a
  Fortran 77 compiler that uses a different symbol mangling scheme.

  NOTE: For platforms that support the multi-Fortran-compiler bindings
  (i.e., weak symbols are supported), due to limitations in the MPI
  standard and in Fortran compilers, it is not possible to hide these
  differences in all cases.  Specifically, the following two cases may
  not be portable between different Fortran compilers:

  1. The C constants MPI_F_STATUS_IGNORE and MPI_F_STATUSES_IGNORE
     will only compare properly to Fortran applications that were
     created with Fortran compilers that that use the same
     name-mangling scheme as the Fortran compiler that Open MPI was
     configured with.

  2. Fortran compilers may have different values for the logical
     .TRUE. constant.  As such, any MPI function that uses the Fortran
     LOGICAL type may only get .TRUE. values back that correspond to
     the the .TRUE. value of the Fortran compiler that Open MPI was
     configured with.  Note that some Fortran compilers allow forcing
     .TRUE. to be 1 and .FALSE. to be 0.  For example, the Portland
     Group compilers provide the "-Munixlogical" option, and Intel
     compilers (version >= 8.) provide the "-fpscomp logicals" option.

  You can use the ompi_info command to see the Fortran compiler that
  Open MPI was configured with.

- The Fortran 90 MPI bindings can now be built in one of three sizes
  using --with-mpi-f90-size=SIZE (see description below).  These sizes
  reflect the number of MPI functions included in the "mpi" Fortran 90
  module and therefore which functions will be subject to strict type
  checking.  All functions not included in the Fortran 90 module can
  still be invoked from F90 applications, but will fall back to
  Fortran-77 style checking (i.e., little/none).

  - trivial: Only includes F90-specific functions from MPI-2.  This
    means overloaded versions of MPI_SIZEOF for all the MPI-supported
    F90 intrinsic types.

  - small (default): All the functions in "trivial" plus all MPI
    functions that take no choice buffers (meaning buffers that are
    specified by the user and are of type (void*) in the C bindings --
    generally buffers specified for message passing).  Hence,
    functions like MPI_COMM_RANK are included, but functions like
    MPI_SEND are not.

  - medium: All the functions in "small" plus all MPI functions that
    take one choice buffer (e.g., MPI_SEND, MPI_RECV, ...).  All
    one-choice-buffer functions have overloaded variants for each of
    the MPI-supported Fortran intrinsic types up to the number of
    dimensions specified by --with-f90-max-array-dim (default value is
    4).

  Increasing the size of the F90 module (in order from trivial, small,
  and medium) will generally increase the length of time required to
  compile user MPI applications.  Specifically, "trivial"- and
  "small"-sized F90 modules generally allow user MPI applications to
  be compiled fairly quickly but lose type safety for all MPI
  functions with choice buffers.  "medium"-sized F90 modules generally
  take longer to compile user applications but provide greater type
  safety for MPI functions.

  Note that MPI functions with two choice buffers (e.g., MPI_GATHER)
  are not currently included in Open MPI's F90 interface.  Calls to
  these functions will automatically fall through to Open MPI's F77
  interface.  A "large" size that includes the two choice buffer MPI
  functions is possible in future versions of Open MPI.


General Run-Time Support Notes
------------------------------

- The Open MPI installation must be in your PATH on all nodes (and
  potentially LD_LIBRARY_PATH, if libmpi is a shared library), unless
  using the --prefix or --enable-mpirun-prefix-by-default
  functionality (see below).

- LAM/MPI-like mpirun notation of "C" and "N" is not yet supported.

- The XGrid support is experimental - see the Open MPI FAQ and this
  post on the Open MPI user's mailing list for more information:

  http://www.open-mpi.org/community/lists/users/2006/01/0539.php

- Open MPI's run-time behavior can be customized via MCA ("MPI
  Component Architecture") parameters (see below for more information
  on how to get/set MCA parameter values).  Some MCA parameters can be
  set in a way that renders Open MPI inoperable (see notes about MCA
  parameters later in this file).  In particular, some parameters have
  required options that must be included.

  - If specified, the "btl" parameter must include the "self"
    component, or Open MPI will not be able to deliver messages to the
    same rank as the sender.  For example: "mpirun --mca btl tcp,self
    ..."
  - If specified, the "btl_tcp_if_exclude" paramater must include the
    loopback device ("lo" on many Linux platforms), or Open MPI will
    not be able to route MPI messages using the TCP BTL.  For example:
    "mpirun --mca btl_tcp_if_exclude lo,eth1 ..."

- Running on nodes with different endian and/or different datatype
  sizes within a single parallel job is supported in this release.
  However, Open MPI does not resize data when datatypes differ in size
  (for example, sending a 4 byte MPI_DOUBLE and receiving an 8 byte
  MPI_DOUBLE will fail).


MPI Functionality and Features
------------------------------

- All MPI-2.1 functionality is supported.

- MPI_THREAD_MULTIPLE support is included, but is only lightly tested.
  It likely does not work for thread-intensive applications.  Note
  that *only* the MPI point-to-point communication functions for the
  BTL's listed above are considered thread safe.  Other support
  functions (e.g., MPI attributes) have not been certified as safe
  when simultaneously used by multiple threads.

  Note that Open MPI's thread support is in a fairly early stage; the
  above devices are likely to *work*, but the latency is likely to be
  fairly high.  Specifically, efforts so far have concentrated on
  *correctness*, not *performance* (yet).

- MPI_REAL16 and MPI_COMPLEX32 are only supported on platforms where a
  portable C datatype can be found that matches the Fortran type
  REAL*16, both in size and bit representation.

- Asynchronous message passing progress using threads can be turned on
  with the --enable-progress-threads option to configure.
  Asynchronous message passing progress is only supported with devices
  that support MPI_THREAD_MULTIPLE, but is only very lightly tested
  (and may not provide very much performance benefit).


Collectives
-----------

- The "hierarch" coll component (i.e., an implementation of MPI
  collective operations) attempts to discover network layers of
  latency in order to segregate individual "local" and "global"
  operations as part of the overall collective operation.  In this
  way, network traffic can be reduced -- or possibly even minimized
  (similar to MagPIe).  The current "hierarch" component only
  separates MPI processes into on- and off-node groups.

  Hierarch has had sufficient correctness testing, but has not
  received much performance tuning.  As such, hierarch is not
  activated by default -- it must be enabled manually by setting its
  priority level to 100:

    mpirun --mca coll_hierarch_priority 100 ...

  We would appreciate feedback from the user community about how well
  hierarch works for your applications.


Network Support
---------------

- The OpenFabrics Enterprise Distribution (OFED) software package v1.0
  will not work properly with Open MPI v1.2 (and later) due to how its
  Mellanox InfiniBand plugin driver is created.  The problem is fixed
  OFED v1.1 (and later).

- Older mVAPI-based InfiniBand drivers (Mellanox VAPI) are no longer
  supported.  Please use an older version of Open MPI (1.2 series or
  earlier) if you need mVAPI support.

- The use of fork() with the openib BTL is only partially supported,
  and only on Linux kernels >= v2.6.15 with libibverbs v1.1 or later
  (first released as part of OFED v1.2), per restrictions imposed by
  the OFED network stack.

- There are two MPI network models available: "ob1" and "cm".  "ob1"
  uses BTL ("Byte Transfer Layer") components for each supported
  network.  "cm" uses MTL ("Matching Tranport Layer") components for
  each supported network.

  - "ob1" supports a variety of networks that can be used in
    combination with each other (per OS constraints; e.g., there are
    reports that the GM and OpenFabrics kernel drivers do not operate
    well together):
    - OpenFabrics: InfiniBand and iWARP
    - Loopback (send-to-self)
    - Myrinet: GM and MX
    - Portals
    - Quadrics Elan
    - Shared memory
    - TCP
    - SCTP
    - uDAPL

  - "cm" supports a smaller number of networks (and they cannot be
    used together), but may provide better better overall MPI
    performance:
    - Myrinet MX (not GM)
    - InfiniPath PSM
    - Portals

  Open MPI will, by default, choose to use "cm" when the InfiniPath
  PSM MTL can be used.  Otherwise, OB1 will be used and the
  corresponding BTLs will be selected.  Users can force the use of ob1
  or cm if desired by setting the "pml" MCA parameter at run-time:

    shell$ mpirun --mca pml ob1 ...
    or
    shell$ mpirun --mca pml cm ...

- Myrinet MX support is shared between the 2 internal devices, the MTL
  and the BTL.  The design of the BTL interface in Open MPI assumes
  that only naive one-sided communication capabilities are provided by
  the low level communication layers.  However, modern communication
  layers such as Myrinet MX, InfiniPath PSM, or Portals, natively
  implement highly-optimized two-sided communication semantics.  To
  leverage these capabilities, Open MPI provides the "cm" PML and
  corresponding MTL components to transfer messages rather than bytes.
  The MTL interface implements a shorter code path and lets the
  low-level network library decide which protocol to use (depending on
  issues such as message length, internal resources and other
  parameters specific to the underlying interconnect).  However, Open
  MPI cannot currently use multiple MTL modules at once.  In the case
  of the MX MTL, process loopback and on-node shared memory
  communications are provided by the MX library.  Moreover, the
  current MX MTL does not support message pipelining resulting in
  lower performances in case of non-contiguous data-types.

The "ob1" PML and BTL components use Open MPI's internal on-node
  shared memory and process loopback devices for high performance.
  The BTL interface allows multiple devices to be used simultaneously.
  For the MX BTL it is recommended that the first segment (which is as
  a threshold between the eager and the rendezvous protocol) should
  always be at most 4KB, but there is no further restriction on the
  size of subsequent fragments.

  The MX MTL is recommended in the common case for best performance on
  10G hardware when most of the data transfers cover contiguous memory
  layouts.  The MX BTL is recommended in all other cases, such as when
  using multiple interconnects at the same time (including TCP), or
  transferring non contiguous data-types.

===========================================================================

Building Open MPI
-----------------

Open MPI uses a traditional configure script paired with "make" to
build.  Typical installs can be of the pattern:

---------------------------------------------------------------------------
shell$ ./configure [...options...]
shell$ make all install
---------------------------------------------------------------------------

There are many available configure options (see "./configure --help"
for a full list); a summary of the more commonly used ones follows:

--prefix=<directory>
  Install Open MPI into the base directory named <directory>.  Hence,
  Open MPI will place its executables in <directory>/bin, its header
  files in <directory>/include, its libraries in <directory>/lib, etc.

--with-elan=<directory>
  Specify the directory where the Quadrics Elan library and header
  files are located.  This option is generally only necessary if the
  Elan headers and libraries are not in default compiler/linker
  search paths.

  Elan is the support library for Quadrics-based networks.

--with-elan-libdir=<directory>
  Look in directory for the Quadrics Elan libraries.  By default, Open
  MPI will look in <elan directory>/lib and <elan directory>/lib64,
  which covers most cases.  This option is only needed for special
  configurations.

--with-gm=<directory>
  Specify the directory where the GM libraries and header files are
  located.  This option is generally only necessary if the GM headers
  and libraries are not in default compiler/linker search paths.

  GM is the support library for older Myrinet-based networks (GM has
  been obsoleted by MX).

--with-gm-libdir=<directory>
  Look in directory for the GM libraries.  By default, Open MPI will
  look in <gm directory>/lib and <gm directory>/lib64, which covers
  most cases.  This option is only needed for special configurations.

--with-mx=<directory>
  Specify the directory where the MX libraries and header files are
  located.  This option is generally only necessary if the MX headers
  and libraries are not in default compiler/linker search paths.

  MX is the support library for Myrinet-based networks.

--with-mx-libdir=<directory>
  Look in directory for the MX libraries.  By default, Open MPI will
  look in <mx directory>/lib and <mx directory>/lib64, which covers
  most cases.  This option is only needed for special configurations.

--with-openib=<directory>
  Specify the directory where the OpenFabrics (previously known as
  OpenIB) libraries and header files are located.  This option is
  generally only necessary if the OpenFabrics headers and libraries
  are not in default compiler/linker search paths.

  "OpenFabrics" refers to iWARP- and InifiniBand-based networks.

--with-openib-libdir=<directory>
  Look in directory for the OpenFabrics libraries.  By default, Open
  MPI will look in <openib directory>/lib and <openib
  directory>/lib64, which covers most cases.  This option is only
  needed for special configurations.

--with-portals=<directory>
  Specify the directory where the Portals libraries and header files
  are located.  This option is generally only necessary if the Portals
  headers and libraries are not in default compiler/linker search
  paths.

  Portals is the support library for Cray interconnects, but is also
  available on other platforms (e.g., there is a Portals library
  implemented over regular TCP).

--with-portals-config=<type>
  Configuration to use for Portals support. The following <type>
  values are possible: "utcp", "xt3", "xt3-modex" (default: utcp).

--with-portals-libs=<libs>
  Additional libraries to link with for Portals support.

--with-psm=<directory>
  Specify the directory where the QLogic InfiniPath PSM library and
  header files are located.  This option is generally only necessary
  if the InfiniPath headers and libraries are not in default
  compiler/linker search paths.

  PSM is the support library for QLogic InfiniPath network adapters.

--with-psm-libdir=<directory>
  Look in directory for the PSM libraries.  By default, Open MPI will
  look in <psm directory>/lib and <psm directory>/lib64, which covers
  most cases.  This option is only needed for special configurations.

--with-sctp=<directory>
  Specify the directory where the SCTP libraries and header files are
  located.  This option is generally only necessary if the SCTP headers
  and libraries are not in default compiler/linker search paths.

  SCTP is a special network stack over ethernet networks.

--with-sctp-libdir=<directory>
  Look in directory for the SCTP libraries.  By default, Open MPI will
  look in <sctp directory>/lib and <sctp directory>/lib64, which covers
  most cases.  This option is only needed for special configurations.

--with-udapl=<directory>
  Specify the directory where the UDAPL libraries and header files are
  located.  Note that UDAPL support is disabled by default on Linux;
  the --with-udapl flag must be specified in order to enable it.
  Specifying the directory argument is generally only necessary if the
  UDAPL headers and libraries are not in default compiler/linker
  search paths.

  UDAPL is the support library for high performance networks in Sun
  HPC ClusterTools and on Linux OpenFabrics networks (although the
  "openib" options are preferred for Linux OpenFabrics networks, not
  UDAPL).

--with-udapl-libdir=<directory>
  Look in directory for the UDAPL libraries.  By default, Open MPI
  will look in <udapl directory>/lib and <udapl directory>/lib64,
  which covers most cases.  This option is only needed for special
  configurations.

--with-lsf=<directory>
  Specify the directory where the LSF libraries and header files are
  located.  This option is generally only necessary if the LSF headers
  and libraries are not in default compiler/linker search paths.

  LSF is a resource manager system, frequently used as a batch
  scheduler in HPC systems.

--with-lsf-libdir=<directory>
  Look in directory for the LSF libraries.  By default, Open MPI will
  look in <lsf directory>/lib and <lsf directory>/lib64, which covers
  most cases.  This option is only needed for special configurations.

--with-tm=<directory>
  Specify the directory where the TM libraries and header files are
  located.  This option is generally only necessary if the TM headers
  and libraries are not in default compiler/linker search paths.

  TM is the support library for the Torque and PBS Pro resource
  manager systems, both of which are frequently used as a batch
  scheduler in HPC systems.

--with-sge
  Specify to build support for the Sun Grid Engine (SGE) resource
  manager.  SGE support is disabled by default; this option must be
  specified to build OMPI's SGE support.

  The Sun Grid Engine (SGE) is a resource manager system, frequently
  used as a batch scheduler in HPC systems.

--with-mpi-param_check(=value)
  "value" can be one of: always, never, runtime.  If --with-mpi-param
  is not specified, "runtime" is the default.  If --with-mpi-param
  is specified with no value, "always" is used.  Using
  --without-mpi-param-check is equivalent to "never".

  - always: the parameters of MPI functions are always checked for
    errors 
  - never: the parameters of MPI functions are never checked for
    errors 
  - runtime: whether the parameters of MPI functions are checked
    depends on the value of the MCA parameter mpi_param_check
    (default: yes).

--with-threads=value
  Since thread support (both support for MPI_THREAD_MULTIPLE and
  asynchronous progress) is only partially tested, it is disabled by
  default.  To enable threading, use "--with-threads=posix".  This is
  most useful when combined with --enable-mpi-threads and/or
  --enable-progress-threads.

--enable-mpi-threads
  Allows the MPI thread level MPI_THREAD_MULTIPLE.  See
  --with-threads; this is currently disabled by default.

--enable-progress-threads
  Allows asynchronous progress in some transports.  See
  --with-threads; this is currently disabled by default.  See the
  above note about asynchronous progress.

--disable-mpi-cxx
  Disable building the C++ MPI bindings.  Note that this does *not*
  disable the C++ checks during configure; some of Open MPI's tools
  are written in C++ and therefore require a C++ compiler to be built.

--disable-mpi-cxx-seek
  Disable the MPI::SEEK_* constants.  Due to a problem with the MPI-2
  specification, these constants can conflict with system-level SEEK_*
  constants.  Open MPI attempts to work around this problem, but the
  workaround may fail in some esoteric situations.  The
  --disable-mpi-cxx-seek switch disables Open MPI's workarounds (and
  therefore the MPI::SEEK_* constants will be unavailable).

--disable-mpi-f77
  Disable building the Fortran 77 MPI bindings.

--disable-mpi-f90
  Disable building the Fortran 90 MPI bindings.  Also related to the
  --with-f90-max-array-dim and --with-mpi-f90-size options.

--with-mpi-f90-size=<SIZE>
  Three sizes of the MPI F90 module can be built: trivial (only a
  handful of MPI-2 F90-specific functions are included in the F90
  module), small (trivial + all MPI functions that take no choice
  buffers), and medium (small + all MPI functions that take 1 choice
  buffer).  This parameter is only used if the F90 bindings are
  enabled.

--with-f90-max-array-dim=<DIM>
  The F90 MPI bindings are strictly typed, even including the number of
  dimensions for arrays for MPI choice buffer parameters.  Open MPI
  generates these bindings at compile time with a maximum number of
  dimensions as specified by this parameter.  The default value is 4.

--enable-mpirun-prefix-by-default
  This option forces the "mpirun" command to always behave as if
  "--prefix $prefix" was present on the command line (where $prefix is
  the value given to the --prefix option to configure).  This prevents
  most rsh/ssh-based users from needing to modify their shell startup
  files to set the PATH and/or LD_LIBRARY_PATH for Open MPI on remote
  nodes.  Note, however, that such users may still desire to set PATH
  -- perhaps even in their shell startup files -- so that executables
  such as mpicc and mpirun can be found without needing to type long
  path names.  --enable-orterun-prefix-by-default is a synonym for
  this option.

--disable-shared
  By default, libmpi is built as a shared library, and all components
  are built as dynamic shared objects (DSOs).  This switch disables
  this default; it is really only useful when used with
  --enable-static.  Specifically, this option does *not* imply
  --enable-static; enabling static libraries and disabling shared
  libraries are two independent options.

--enable-static
  Build libmpi as a static library, and statically link in all
  components.  Note that this option does *not* imply
  --disable-shared; enabling static libraries and disabling shared
  libraries are two independent options.

--enable-sparse-groups
  Enable the usage of sparse groups. This would save memory
  significantly especially if you are creating large
  communicators. (Disabled by default)

--enable-peruse
  Enable the PERUSE MPI data analysis interface.

--enable-dlopen
  Build all of Open MPI's components as standalone Dynamic Shared
  Objects (DSO's) that are loaded at run-time.  The opposite of this
  option, --disable-dlopen, causes two things: 

  1. All of Open MPI's components will be built as part of Open MPI's
     normal libraries (e.g., libmpi).  
  2. Open MPI will not attempt to open any DSO's at run-time.

  Note that this option does *not* imply that OMPI's libraries will be
  built as static objects (e.g., libmpi.a).  It only specifies the
  location of OMPI's components: standalone DSOs or folded into the
  Open MPI libraries.  You can control whenther Open MPI's libraries
  are build as static or dynamic via --enable|disable-static and
  --enable|disable-shared.

--enable-heterogeneous
  Enable support for running on heterogeneous clusters (e.g., machines
  with different endian representations).  Heterogeneous support is
  disabled by default because it imposes a minor performance penalty.

--enable-ptmalloc2-internal
  ***NOTE: This option no longer exists.

  This option was introduced in Open MPI v1.3 and was then removed in
  Open MPI v1.3.2.  Open MPI fundamentally changed how it uses
  ptmalloc2 support in v1.3.2 such that the
  --enable-ptmalloc2-internal flag was no longer necessary.  It can
  still harmlessly be supplied to Open MPI's configure script, but a
  warning will appear about how it is an unrecognized option.

  In v1.3 and v1.3.1, Open MPI built the ptmalloc2 library as a
  standalone library that users could choose to link in or not (by
  adding -lopenmpi-malloc to their link command).  Using this option
  restored pre-v1.3 behavior of *always* forcing the user to use the
  ptmalloc2 memory manager (because it is part of libmpi).

  Starting with v1.3.2, ptmalloc2 is always built into Open MPI, but
  is only activated in certain scenarios.

--with-wrapper-cflags=<cflags>
--with-wrapper-cxxflags=<cxxflags>
--with-wrapper-fflags=<fflags>
--with-wrapper-fcflags=<fcflags>
--with-wrapper-ldflags=<ldflags>
--with-wrapper-libs=<libs>
  Add the specified flags to the default flags that used are in Open
  MPI's "wrapper" compilers (e.g., mpicc -- see below for more
  information about Open MPI's wrapper compilers).  By default, Open
  MPI's wrapper compilers use the same compilers used to build Open
  MPI and specify an absolute minimum set of additional flags that are
  necessary to compile/link MPI applications.  These configure options
  give system administrators the ability to embed additional flags in
  OMPI's wrapper compilers (which is a local policy decision).  The
  meanings of the different flags are:

  <cflags>: Flags passed by the mpicc wrapper to the C compiler
  <cxxflags>: Flags passed by the mpic++ wrapper to the C++ compiler
  <fflags>: Flags passed by the mpif77 wrapper to the F77 compiler
  <fcflags>: Flags passed by the mpif90 wrapper to the F90 compiler
  <ldflags>: Flags passed by all the wrappers to the linker
  <libs>: Flags passed by all the wrappers to the linker

  There are other ways to configure Open MPI's wrapper compiler
  behavior; see the Open MPI FAQ for more information.

There are many other options available -- see "./configure --help".

Changing the compilers that Open MPI uses to build itself uses the
standard Autoconf mechanism of setting special environment variables
either before invoking configure or on the configure command line.
The following environment variables are recognized by configure:

CC          - C compiler to use
CFLAGS      - Compile flags to pass to the C compiler
CPPFLAGS    - Preprocessor flags to pass to the C compiler

CXX         - C++ compiler to use
CXXFLAGS    - Compile flags to pass to the C++ compiler
CXXCPPFLAGS - Preprocessor flags to pass to the C++ compiler

F77         - Fortran 77 compiler to use
FFLAGS      - Compile flags to pass to the Fortran 77 compiler

FC          - Fortran 90 compiler to use
FCFLAGS     - Compile flags to pass to the Fortran 90 compiler

LDFLAGS     - Linker flags to pass to all compilers
LIBS        - Libraries to pass to all compilers (it is rarely
              necessary for users to need to specify additional LIBS)

For example:

shell$ ./configure CC=mycc CXX=myc++ F77=myf77 F90=myf90 ...

***Note: We generally suggest using the above command line form for
   setting different compilers (vs. setting environment variables and
   then invoking "./configure").  The above form will save all
   variables and values in the config.log file, which makes
   post-mortem analysis easier when problems occur.

It is required that the compilers specified be compile and link
compatible, meaning that object files created by one compiler must be
able to be linked with object files from the other compilers and
produce correctly functioning executables.

Open MPI supports all the "make" targets that are provided by GNU
Automake, such as:

all       - build the entire Open MPI package
install   - install Open MPI
uninstall - remove all traces of Open MPI from the $prefix
clean     - clean out the build tree

Once Open MPI has been built and installed, it is safe to run "make
clean" and/or remove the entire build tree.

VPATH and parallel builds are fully supported.

Generally speaking, the only thing that users need to do to use Open
MPI is ensure that <prefix>/bin is in their PATH and <prefix>/lib is
in their LD_LIBRARY_PATH.  Users may need to ensure to set the PATH
and LD_LIBRARY_PATH in their shell setup files (e.g., .bashrc, .cshrc)
so that non-interactive rsh/ssh-based logins will be able to find the
Open MPI executables.

===========================================================================

Checking Your Open MPI Installation
-----------------------------------

The "ompi_info" command can be used to check the status of your Open
MPI installation (located in <prefix>/bin/ompi_info).  Running it with
no arguments provides a summary of information about your Open MPI
installation.   

Note that the ompi_info command is extremely helpful in determining
which components are installed as well as listing all the run-time
settable parameters that are available in each component (as well as
their default values).

The following options may be helpful:

--all       Show a *lot* of information about your Open MPI
            installation. 
--parsable  Display all the information in an easily
            grep/cut/awk/sed-able format.
--param <framework> <component>
            A <framework> of "all" and a <component> of "all" will
            show all parameters to all components.  Otherwise, the
            parameters of all the components in a specific framework,
            or just the parameters of a specific component can be
            displayed by using an appropriate <framework> and/or
            <component> name.

Changing the values of these parameters is explained in the "The
Modular Component Architecture (MCA)" section, below.

===========================================================================

Compiling Open MPI Applications
-------------------------------

Open MPI provides "wrapper" compilers that should be used for
compiling MPI applications:

C:          mpicc
C++:        mpiCC (or mpic++ if your filesystem is case-insensitive)
Fortran 77: mpif77
Fortran 90: mpif90

For example:

shell$ mpicc hello_world_mpi.c -o hello_world_mpi -g
shell$

All the wrapper compilers do is add a variety of compiler and linker
flags to the command line and then invoke a back-end compiler.  To be
specific: the wrapper compilers do not parse source code at all; they
are solely command-line manipulators, and have nothing to do with the
actual compilation or linking of programs.  The end result is an MPI
executable that is properly linked to all the relevant libraries.

Customizing the behavior of the wrapper compilers is possible (e.g.,
changing the compiler [not recommended] or specifying additional
compiler/linker flags); see the Open MPI FAQ for more information.

===========================================================================

Running Open MPI Applications
-----------------------------

Open MPI supports both mpirun and mpiexec (they are exactly
equivalent).  For example:

shell$ mpirun -np 2 hello_world_mpi
or
shell$ mpiexec -np 1 hello_world_mpi : -np 1 hello_world_mpi

are equivalent.  Some of mpiexec's switches (such as -host and -arch)
are not yet functional, although they will not error if you try to use
them.  

The rsh launcher accepts a -hostfile parameter (the option
"-machinefile" is equivalent); you can specify a -hostfile parameter
indicating an standard mpirun-style hostfile (one hostname per line):

shell$ mpirun -hostfile my_hostfile -np 2 hello_world_mpi

If you intend to run more than one process on a node, the hostfile can
use the "slots" attribute.  If "slots" is not specified, a count of 1
is assumed.  For example, using the following hostfile:

---------------------------------------------------------------------------
node1.example.com
node2.example.com
node3.example.com slots=2
node4.example.com slots=4
---------------------------------------------------------------------------

shell$ mpirun -hostfile my_hostfile -np 8 hello_world_mpi

will launch MPI_COMM_WORLD rank 0 on node1, rank 1 on node2, ranks 2
and 3 on node3, and ranks 4 through 7 on node4.

Other starters, such as the resource manager / batch scheduling
environments, do not require hostfiles (and will ignore the hostfile
if it is supplied).  They will also launch as many processes as slots
have been allocated by the scheduler if no "-np" argument has been
provided.  For example, running a SLURM job with 8 processors:

shell$ salloc -n 8 mpirun a.out

The above command will reserve 8 processors and run 1 copy of mpirun,
which will, in turn, launch 8 copies of a.out in a single
MPI_COMM_WORLD on the processors that were allocated by SLURM.

Note that the values of component parameters can be changed on the
mpirun / mpiexec command line.  This is explained in the section
below, "The Modular Component Architecture (MCA)".

===========================================================================

The Modular Component Architecture (MCA)

The MCA is the backbone of Open MPI -- most services and functionality
are implemented through MCA components.  Here is a list of all the
component frameworks in Open MPI:

---------------------------------------------------------------------------

MPI component frameworks:
-------------------------

allocator - Memory allocator
bml       - BTL management layer
btl       - MPI point-to-point Byte Transfer Layer, used for MPI
            point-to-point messages on some types of networks
coll      - MPI collective algorithms
crcp      - Checkpoint/restart coordination protocol
dpm       - MPI-2 dynamic process management
io        - MPI-2 I/O
mpool     - Memory pooling
mtl       - Matching transport layer, used for MPI point-to-point
            messages on some types of networks
osc       - MPI-2 one-sided communications
pml       - MPI point-to-point management layer
pubsub    - MPI-2 publish/subscribe management
rcache    - Memory registration cache
topo      - MPI topology routines

Back-end run-time environment component frameworks:
---------------------------------------------------

errmgr    - RTE error manager
ess       - RTE environment-specfic services
filem     - Remote file management
grpcomm   - RTE group communications
iof       - I/O forwarding
notifier  - System/network administrator noficiation system
odls      - OpenRTE daemon local launch subsystem
oob       - Out of band messaging
plm       - Process lifecycle management
ras       - Resource allocation system
rmaps     - Resource mapping system
rml       - RTE message layer
routed    - Routing table for the RML
snapc     - Snapshot coordination

Miscellaneous frameworks:
-------------------------

backtrace   - Debugging call stack backtrace support
carto       - Cartography (host/network mapping) support
crs         - Checkpoint and restart service
installdirs - Installation directory relocation services
maffinity   - Memory affinity
memchecker  - Run-time memory checking
memcpy      - Memopy copy support
memory      - Memory management hooks
paffinity   - Processor affinity
timer       - High-resolution timers

---------------------------------------------------------------------------

Each framework typically has one or more components that are used at
run-time.  For example, the btl framework is used by the MPI layer to
send bytes across different types underlying networks.  The tcp btl,
for example, sends messages across TCP-based networks; the openib btl
sends messages across OpenFabrics-based networks; the MX btl sends
messages across Myrinet networks.

Each component typically has some tunable parameters that can be
changed at run-time.  Use the ompi_info command to check a component
to see what its tunable parameters are.  For example:

shell$ ompi_info --param btl tcp

shows all the parameters (and default values) for the tcp btl
component.

These values can be overridden at run-time in several ways.  At
run-time, the following locations are examined (in order) for new
values of parameters:

1. <prefix>/etc/openmpi-mca-params.conf

   This file is intended to set any system-wide default MCA parameter
   values -- it will apply, by default, to all users who use this Open
   MPI installation.  The default file that is installed contains many
   comments explaining its format.

2. $HOME/.openmpi/mca-params.conf

   If this file exists, it should be in the same format as
   <prefix>/etc/openmpi-mca-params.conf.  It is intended to provide
   per-user default parameter values.

3. environment variables of the form OMPI_MCA_<name> set equal to a
   <value>

   Where <name> is the name of the parameter.  For example, set the
   variable named OMPI_MCA_btl_tcp_frag_size to the value 65536
   (Bourne-style shells):

   shell$ OMPI_MCA_btl_tcp_frag_size=65536
   shell$ export OMPI_MCA_btl_tcp_frag_size

4. the mpirun command line: --mca <name> <value>
 
   Where <name> is the name of the parameter.  For example:

   shell$ mpirun --mca btl_tcp_frag_size 65536 -np 2 hello_world_mpi

These locations are checked in order.  For example, a parameter value
passed on the mpirun command line will override an environment
variable; an environment variable will override the system-wide
defaults.

===========================================================================

Common Questions
----------------

Many common questions about building and using Open MPI are answered
on the FAQ:

    http://www.open-mpi.org/faq/

===========================================================================

Got more questions?
-------------------

Found a bug?  Got a question?  Want to make a suggestion?  Want to
contribute to Open MPI?  Please let us know!

When submitting questions and problems, be sure to include as much
extra information as possible.  This web page details all the
information that we request in order to provide assistance:

     http://www.open-mpi.org/community/help/

User-level questions and comments should generally be sent to the
user's mailing list (users@open-mpi.org).  Because of spam, only
subscribers are allowed to post to this list (ensure that you
subscribe with and post from *exactly* the same e-mail address --
joe@example.com is considered different than
joe@mycomputer.example.com!).  Visit this page to subscribe to the
user's list:

     http://www.open-mpi.org/mailman/listinfo.cgi/users

Developer-level bug reports, questions, and comments should generally
be sent to the developer's mailing list (devel@open-mpi.org).  Please
do not post the same question to both lists.  As with the user's list,
only subscribers are allowed to post to the developer's list.  Visit
the following web page to subscribe:

     http://www.open-mpi.org/mailman/listinfo.cgi/devel

Make today an Open MPI day!
