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README
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Copyright (c) 2004-2007 The Trustees of Indiana University and Indiana
University Research and Technology
Corporation. All rights reserved.
Copyright (c) 2004-2007 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) 2006-2012 Cisco Systems, Inc. All rights reserved.
Copyright (c) 2006-2011 Mellanox Technologies. All rights reserved.
Copyright (c) 2006-2012 Oracle and/or its affiliates. All rights reserved.
Copyright (c) 2007 Myricom, Inc. All rights reserved.
Copyright (c) 2008 IBM Corporation. All rights reserved.
Copyright (c) 2010 Oak Ridge National Labs. All rights reserved.
Copyright (c) 2011 University of Houston. All rights reserved.
$COPYRIGHT$
Additional copyrights may follow
$HEADER$
===========================================================================
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/
===========================================================================
The following abbreviated list of release notes applies to this code
base as of this writing (22 February 2012):
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, Torque
- Platform LSF (v7.0.2 and later)
- SLURM
- Cray XT-3, XT-4, and XT-5
- Oracle Grid Engine (OGE) 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 Oracle
Solaris Studio 12
- Linux (various flavors/distros), 64 bit (x86), with gcc, Absoft,
Intel, Portland, and Oracle Solaris Studio 12.3 compilers (*)
- OS X (10.5, 10.6, 10.7), 32 and 64 bit (x86_64), with gcc and
Absoft compilers (*)
- Oracle Solaris 10 and 11, 32 and 64 bit (SPARC, i386, x86_64),
with Oracle Solaris Studio 12.2 and 12.3
(*) 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);
see the README.WINDOWS file.
Compiler Notes
--------------
- Mixing compilers from different vendors when building Open MPI
(e.g., using the C/C++ compiler from one vendor and the Fortran
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.
- In general, the latest versions of compilers of a given vendor's
series have the least bugs. We have seen cases where Vendor XYZ's
compiler version A.B fails to compile Open MPI, but version A.C
(where C>B) works just fine. If you run into a compile failure, you
might want to double check that you have the latest bug fixes and
patches for your compiler.
- Absoft 11.5.2 plus a service pack from September 2012 (which Absoft
says is available upon request), or a version later than 11.5.2
(e.g., 11.5.3), is required to compile the new Fortran mpi_f08
module.
- Open MPI does not support the Sparc v8 CPU target. However,
as of Solaris Studio 12.1, and later compilers, one should not
specify -xarch=v8plus or -xarch=v9. The use of the options
-m32 and -m64 for producing 32 and 64 bit targets, respectively,
are now preferred by the Solaris Studio compilers.
- It has been noticed that if one uses CXX=sunCC, in which sunCC
is a link in the Solaris Studio compiler release, that the OMPI
build system has issue with sunCC and does not build libmpi_cxx.so.
Therefore the make install fails. So we suggest that one should
use CXX=CC, which works, instead of CXX=sunCC.
- If one tries to build OMPI on Ubuntu with Solaris Studio using the C++
compiler and the -m32 option, you might see a warning:
CC: Warning: failed to detect system linker version, falling back to
custom linker usage
And the build will fail. One can overcome this error by either
setting LD_LIBRARY_PATH to the location of the 32 bit libraries (most
likely /lib32), or giving LDFLAGS="-L/lib32 -R/lib32" to the configure
command. Officially, Solaris Studio is not supported on Ubuntu Linux
distributions, so additional problems might be incurred.
- The Solaris Studio 12.2 compilers may have a problem compiling
VampirTrace on some Linux platforms. You can either upgrade to a
later version of the Solaris Studio compilers (e.g., 12.3 does not
have this problem), or disable building VampirTrace.
- Open MPI does not support the gccfss compiler (GCC For SPARC
Systems; a now-defunct compiler project from Sun).
- 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.
- It has been reported that the Intel 9.1 and 10.0 compilers fail to
compile Open MPI on IA64 platforms. As of 12 Sep 2012, there is
very little (if any) testing performed on IA64 platforms (with any
compiler). Support is "best effort" for these platforms, but it is
doubtful that any effort will be expended to fix the Intel 9.1 /
10.0 compiler issuers on this platform.
- Early versions of the Intel 12.1 Linux compiler suite on x86_64 seem
to have a bug that prevents Open MPI from working. Symptoms
including immediate segv of the wrapper compilers (e.g., mpicc) and
MPI applications. As of 1 Feb 2012, if you upgrade to the latest
version of the Intel 12.1 Linux compiler suite, the problem will go
away.
- 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 older versions of the Pathscale
compiler on some platforms is an old issue that seems to be a
problem when Pathscale uses a back-end GCC 3.x compiler. Here's a
proposed solution from the Pathscale support team (from July 2010):
The proposed work-around is to install gcc-4.x on the system and
use the pathCC -gnu4 option. Newer versions of the compiler (4.x
and beyond) should have this fixed, but we'll have to test to
confirm it's actually fixed and working correctly.
We don't anticipate that this will be much of a problem for Open MPI
users these days (our informal testing shows that not many users are
still using GCC 3.x). Contact Pathscale support if you continue to
have problems with Open MPI's C++ bindings.
- There is currently a known issue with the PGI compilers on OS X
Lion. See https://svn.open-mpi.org/trac/ompi/ticket/3011.
- Using the Absoft compiler to build the MPI Fortran bindings on Suse
9.3 is known to fail due to a Libtool compatibility issue.
- MPI Fortran API support has been completely overhauled since the
Open MPI v1.5/v1.6 series.
********************************************************************
********************************************************************
*** There is now only a single Fortran MPI wrapper compiler:
*** mpifort. mpif77 and mpif90 still exist, but they are symbolic
*** links to mpifort.
********************************************************************
*** Similarly, Open MPI's configure script only recongizes the FC
*** and FCFLAGS environment variables (to specify the Fortran
*** compiler and compiler flags, respectively). The F77 and FFLAGS
*** environment variables are IGNORED.
********************************************************************
********************************************************************
You can use ompi_info to see with which Fortran compiler Open MPI
was configured and compiled.
There are up to three sets of Fortran MPI bindings that may be
provided (depending on your Fortran compiler):
- mpif.h: This is the first MPI Fortran interface that was defined
in MPI-1. It is a file that is included in Fortran source code.
Open MPI's mpif.h does not declare any MPI subroutines; they are
all implicit.
- mpi module: The mpi module file was added in MPI-2. It provides
strong compile-time parameter type checking for MPI subroutines.
- mpi_f08 module: The mpi_f08 module was added in MPI-3. It
provides many advantages over the mpif.h file and mpi module. For
example, MPI handles have distinct types (vs. all being integers).
See the MPI-3 document for more details.
*** The mpi_f08 module is STRONGLY is recommended for all new MPI
Fortran subroutines and applications. Note that the mpi_f08
module can be used in conjunction with the other two Fortran
MPI bindings in the same application (only one binding can be
used per subroutine/function, however). Full interoperability
between mpif.h/mpi module and mpi_f08 module MPI handle types
is provided, allowing mpi_f08 to be used in new subroutines in
legacy MPI applications.
The following notes apply to the above-listed Fortran bindings:
- The mpi_f08 module is new and has been tested with the Intel
Fortran compiler. Other modern Fortran compilers may also work
(but are, as yet, currently untested). It is expected that this
support will mature over time.
The gfortran compiler is *not* supported with the mpi_f08 module
(gfortran lacks some necessary modern Fortran features, sorry).
- All Fortran compilers support the mpif.h-based bindings.
- If Open MPI is built with a non-GNU Fortran compiler, all MPI
subroutines will be prototyped in the mpi module, meaning that all
calls to MPI subroutines will have their parameter types checked
at compile time.
- If Open MPI is built with a GNU Fortran compiler (gfortran), it
will compile a limited "mpi" module -- not all MPI subroutines
will be prototyped due to both poor design of the mpi module in
the MPI-2 specification and a lack of features in gfortran.
Specifically, all MPI subroutines with no "choice" buffers are
prototyped and will receive strong parameter type checking at
run-time (e.g., MPI_INIT, MPI_COMM_RANK, etc.).
MPI subroutines with one choice buffer (e.g., MPI_SEND) are
prototyped for all intrinsic Fortran types for scalars and ranks 1
through 4 (the --with-gfortran-max-array-dim configure switch can
be used to increase the max array rank supported to up to 7).
MPI subroutines with two choice buffers (e.g., MPI_GATHER) are
*not* prototyped. These subroutines can still be called in MPI
applications; they just will not receive strong parameter type
checking.
General Run-Time Support Notes
------------------------------
- The Open MPI installation must be in your PATH on all nodes (and
potentially LD_LIBRARY_PATH (or DYLD_LIBRARY_PATH), if libmpi is a
shared library), unless using the --prefix or
--enable-mpirun-prefix-by-default functionality (see below).
- 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.
- When using MPI deprecated functions, some compilers will emit
warnings. For example:
shell$ cat deprecated_example.c
#include <mpi.h>
void foo(void) {
MPI_Datatype type;
MPI_Type_struct(1, NULL, NULL, NULL, &type);
}
shell$ mpicc -c deprecated_example.c
deprecated_example.c: In function 'foo':
deprecated_example.c:4: warning: 'MPI_Type_struct' is deprecated (declared at /opt/openmpi/include/mpi.h:1522)
shell$
- 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 here are considered thread safe. Other support
functions (e.g., MPI attributes) have not been certified as safe
when simultaneously used by multiple threads.
- tcp
- sm
- mx
- elan
- self
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.
- The "libompitrace" library is bundled in Open MPI and is installed
by default (it can be disabled via the --disable-libompitrace
flag). This library provides a simplistic tracing of select MPI
function calls via the MPI profiling interface. Linking it in to
your appliation via (e.g., via -lompitrace) will automatically
output to stderr when some MPI functions are invoked:
shell$ mpicc hello_world.c -o hello_world -lompitrace
shell$ mpirun -np 1 hello_world.c
MPI_INIT: argc 1
Hello, world, I am 0 of 1
MPI_BARRIER[0]: comm MPI_COMM_WORLD
MPI_FINALIZE[0]
shell$
Keep in mind that the output from the trace library is going to
stderr, so it may output in a slightly different order than the
stdout from your application.
This library is being offered as a "proof of concept" / convenience
from Open MPI. If there is interest, it is trivially easy to extend
it to printf for other MPI functions. Patches and/or suggestions
would be greatfully appreciated on the Open MPI developer's list.
- ROMIO is not supported on OpenBSD. You will need to specify the
--disable-io-romio flag to configure when building on OpenBSD.
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.
- The "fca" coll component: the Mellanox Fabric Collective Accelerator
(FCA) is a solution for offloading collective operations from the
MPI process onto Mellanox QDR InfiniBand switch CPUs and HCAs.
- The "ML" coll component is an implementation of MPI collective
operations that takes advantage of communication hierarchies
in modern systems. A ML collective operation is implemented by
combining multiple independently progressing collective primitives
implemented over different communication hierarchies, hence a ML
collective operation is also reffered to as a hierarchical collective
operation. The number of collective primitives that are included in a
ML collective operation is a function of subgroups(hierarchies).
Typically, MPI processes in a single communication hierarchy such as
CPU socket, node, or subnet are grouped together into a single subgroup
(hierarchy). The number of subgroups are configurable at runtime,
and each different collective operation could be configured to have
a different of number of subgroups.
The component frameworks and components used by\required for a
"ML" collective operation.
Frameworks:
* "sbgp" - Provides functionality for grouping processes into subgroups
* "bcol" - Provides collective primitives optimized for a particular
communication hierarchy
Components:
* sbgp components - Provides grouping functionality over a CPU socket
("basesocket"), shared memory ("basesmuma"),
Mellanox's ConnectX HCA ("ibnet"), and other
interconnects supported by PML ("p2p")
* BCOL components - Provides optimized collective primitives for
shared memory ("basesmuma"), Mellanox's ConnectX
HCA ("iboffload"), and other interconnects supported
by PML ("ptpcoll")
* "ofacm" - Provides connection manager functionality for
InfiniBand communications
* "verbs" - Provides commonly used verbs utilities
* "netpatterns" - Provides an implementation of algorithm patterns
* "commpatterns" - Provides collectives for bootstrap
Network Support
---------------
- There are three MPI network models available: "ob1", "csum", and
"cm". "ob1" and "csum" use 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, iWARP, and RoCE
- Loopback (send-to-self)
- Myrinet MX and Open-MX
- Portals
- Quadrics Elan
- Shared memory
- TCP
- SCTP
- uDAPL
- Windows Verbs
- "csum" is exactly the same as "ob1", except that it performs
additional data integrity checks to ensure that the received data
is intact (vs. trusting the underlying network to deliver the data
correctly). csum supports all the same networks as ob1, but there
is a performance penalty for the additional integrity checks.
- "cm" supports a smaller number of networks (and they cannot be
used together), but may provide better better overall MPI
performance:
- Myrinet MX and Open-MX
- InfiniPath PSM
- Mellanox MXM
- Portals
Open MPI will, by default, choose to use "cm" when the InfiniPath
PSM or the Mellanox MXM MTL can be used. Otherwise, "ob1" will be
used and the corresponding BTLs will be selected. "csum" will never
be selected by default. 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 csum ...
or
shell$ mpirun --mca pml cm ...
- MXM is a MellanoX Messaging library utilizing full range of IB
transports to provide the following messaging services to the upper
level MPI:
- Usage of all available IB transports
- Native RDMA support
- Progress thread
- Shared memory communication
- Hardware-assisted reliability
- 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).
- Better memory management support is available for OFED-based
transports using the "ummunotify" Linux kernel module. OFED memory
managers are necessary for better bandwidth when re-using the same
buffers for large messages (e.g., benchmarks and some applications).
Unfortunately, the ummunotify module was not accepted by the Linux
kernel community (and is still not distributed by OFED). But it
still remains the best memory management solution for MPI
applications that used the OFED network transports. If Open MPI is
able to find the <linux/ummunotify.h> header file, it will build
support for ummunotify and include it by default. If MPI processes
then find the ummunotify kernel module loaded and active, then ther
memory managers (which have been shown to be problematic in some
cases) will be disabled and ummunotify will be used. Otherwise, the
same memory managers from prior versions of Open MPI will be used.
The ummunotify Linux kernel module can be downloaded from:
http://lwn.net/Articles/343351/
- 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 OpenFabrics-based networks (i.e., 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.
- Myrinet MX (and Open-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" and "csum" PMLs 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.
- Older Myrinet "GM" support is no longer available in the v1.5
series. Older versions of Open MPI can be used if GM support is
still needed.
- Linux "knem" support is used when the "sm" (shared memory) BTL is
compiled with knem support (see the --with-knem configure option)
and the knem Linux module is loaded in the running kernel. If the
knem Linux kernel module is not loaded, the knem support is (by
default) silently deactivated during Open MPI jobs.
See http://runtime.bordeaux.inria.fr/knem/ for details on Knem.
Open MPI Extensions
-------------------
- An MPI "extensions" framework has been added (but is not enabled by
default). See the "Open MPI API Extensions" section below for more
information on compiling and using MPI extensions.
- The following extensions are included in this version of Open MPI:
- affinity: Provides the OMPI_Affinity_str() routine on retrieving
a string that contains what resources a process is bound to. See
its man page for more details.
- cr: Provides routines to access to checkpoint restart routines.
See ompi/mpiext/cr/mpiext_cr_c.h for a listing of availble
functions.
- example: A non-functional extension; its only purpose is to
provide an example for how to create other extensions.
===========================================================================
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:
INSTALLATION OPTIONS
--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.
--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.
Be sure to read the description of --without-memory-manager, below;
it may have some effect on --enable-static.
--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 whether Open MPI's libraries
are build as static or dynamic via --enable|disable-static and
--enable|disable-shared.
--with-platform=FILE
Load configure options for the build from FILE. Options on the
command line that are not in FILE are also used. Options on the
command line and in FILE are replaced by what is in FILE.
NETWORKING SUPPORT / OPTIONS
--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-fca=<directory>
Specify the directory where the Mellanox FCA library and
header files are located.
FCA is the support library for Mellanox QDR switches and HCAs.
--with-knem=<directory>
Specify the directory where the knem libraries and header files are
located. This option is generally only necessary if the knem headers
and libraries are not in default compiler/linker search paths.
knem is a Linux kernel module that allows direct process-to-process
memory copies (optionally using hardware offload), potentially
increasing bandwidth for large messages sent between messages on the
same server. See http://runtime.bordeaux.inria.fr/knem/ for
details.
--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. An open
source software package named Open-MX provides the same
functionality on Ethernet-based clusters (Open-MX can provide
MPI performance improvements compared to TCP messaging).
--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-mxm=<directory>
Specify the directory where the Mellanox MXM library and header
files are located. This option is generally only necessary if the
MXM headers and libraries are not in default compiler/linker search
paths.
MXM is the support library for Mellanox Network adapters.
--with-mxm-libdir=<directory>
Look in directory for the MXM libraries. By default, Open MPI will
look in <mxm directory>/lib and <mxm directory>/lib64, which covers
most cases. This option is only needed for special configurations.
--with-verbs=<directory>
Specify the directory where the verbs (also know as OpenFabrics, and
previously known as OpenIB) libraries and header files are located.
This option is generally only necessary if the verbs headers and
libraries are not in default compiler/linker search paths.
"OpenFabrics" refers to iWARP-, RoCE- (aka "IBoIP"), and
InfiniBand-based networks.
--with-verbs-libdir=<directory>
Look in directory for the verbs 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-openib=<directory>
DEPRECATED synonym for --with-verbs.
--with-openib-libdir=<directory>
DEPRECATED synonym for --with-verbs-libdir.
--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 Oracle
Message Passing Toolkit, and also available on Linux OpenFabrics
networks (although the "openib" options are preferred for Linux
OpenFabrics networks, not UDAPL). To be clear: the UDAPL BTL is
*not* recommended for Linux/OpenFabrics platforms.
--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.
RUN-TIME SYSTEM SUPPORT
--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.
--with-alps
Force the building of for the Cray Alps run-time environment. If
Alps support cannot be found, configure will abort.
--with-cray-pmi-ext
Include Cray PMI2 extensions.
--with-loadleveler
Force the building of LoadLeveler scheduler support. If LoadLeveler
support cannot be found, configure will abort.
--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.
NOTE: If you are using LSF version 7.0.5, you will need to add
"LIBS=-ldl" to the configure command line. For example:
./configure LIBS=-ldl --with-lsf ...
This workaround should *only* be needed for LSF 7.0.5.
--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-pmi
Build PMI support (by default, it is not built). If PMI support
cannot be found, configure will abort.
--with-slurm
Force the building of SLURM scheduler support. If SLURM support
cannot be found, configure will abort.
--with-sge
Specify to build support for the Oracle Grid Engine (OGE) resource
manager and/or the open Grid Engine. OGE support is disabled by
default; this option must be specified to build OMPI's OGE support.
The Oracle Grid Engine (OGE) and open Grid Engine packages are
resource manager systems, frequently used as a batch scheduler in
HPC systems.
--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.
MISCELLANEOUS SUPPORT LIBRARIES
--with-blcr=<directory>
Specify the directory where the Berkeley Labs Checkpoint / Restart
(BLCR) libraries and header files are located. This option is
generally only necessary if the BLCR headers and libraries are not
in default compiler/linker search paths.
This option is only meaningful if the --with-ft option is also used
to active Open MPI's fault tolerance behavior.
--with-blcr-libdir=<directory>
Look in directory for the BLCR libraries. By default, Open MPI will
look in <blcr directory>/lib and <blcr directory>/lib64, which
covers most cases. This option is only needed for special
configurations.
--with-dmtcp=<directory>
Specify the directory where the Distributed MultiThreaded
Checkpointing (DMTCP) libraries and header files are located. This
option is generally only necessary if the DMTCP headers and
libraries are not in default compiler/linker search paths.
This option is only meaningful if the --with-ft option is also used
to active Open MPI's fault tolerance behavior.
--with-dmtcp-libdir=<directory>
Look in directory for the DMTCP libraries. By default, Open MPI
will look in <dmtcp directory>/lib and <dmtcp directory>/lib64,
which covers most cases. This option is only needed for special
configurations.
--with-esmtp=<directory>
Specify the directory where the libESMTP libraries and header files are
located. This option is generally only necessary of the libESMTP
headers and libraries are not included in the default
compiler/linker search paths.
libESMTP is a support library for sending e-mail.
--with-ftb=<directory>
Specify the directory where the Fault Tolerant Backplane (FTB)
libraries and header files are located. This option is generally
only necessary if the BLCR headers and libraries are not in default
compiler/linker search paths.
--with-ftb-libdir=<directory>
Look in directory for the FTB libraries. By default, Open MPI will
look in <ftb directory>/lib and <ftb directory>/lib64, which covers
most cases. This option is only needed for special configurations.
--with-hwloc=<location>
Build hwloc support. If <location> is "internal", Open MPI's
internal copy of hwloc is used. If <location> is "external", Open
MPI will search in default locations for an hwloc installation.
Finally, if <location> is a directory, that directory will be
searched for a valid hwloc installation, just like other
--with-FOO=<directory> configure options.
hwloc is a support library that provides processor and memory
affinity information for NUMA platforms.
--with-hwloc-libdir=<directory>
Look in directory for the hwloc libraries. This option is only
usable when building Open MPI against an external hwloc
installation. Just like other --with-FOO-libdir configure options,
this option is only needed for special configurations.
--disable-hwloc-pci
Disable building hwloc's PCI device-sensing capabilities. On some
platforms (e.g., SusE 10 SP1, x86-64), the libpci support library is
broken. Open MPI's configure script should usually detect when
libpci is not usable due to such brokenness and turn off PCI
support, but there may be cases when configure mistakenly enables
PCI support in the presence of a broken libpci. These cases may
result in "make" failing with warnings about relocation symbols in
libpci. The --disable-hwloc-pci switch can be used to force Open
MPI to not build hwloc's PCI device-sensing capabilities in these
cases.
Similarly, if Open MPI incorrectly decides that libpci is broken,