<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="Docutils 0.5: http://docutils.sourceforge.net/" />
<title>HISTORY: MPI for Python</title>
<meta name="author" content="Lisandro Dalcin" />
<meta name="organization" content="CIMEC <http://www.cimec.org.ar>" />
<style type="text/css">
/*
:Author: David Goodger (goodger@python.org)
:Id: $Id: html4css1.css 5196 2007-06-03 20:25:28Z wiemann $
:Copyright: This stylesheet has been placed in the public domain.
Default cascading style sheet for the HTML output of Docutils.
See http://docutils.sf.net/docs/howto/html-stylesheets.html for how to
customize this style sheet.
*/
/* used to remove borders from tables and images */
.borderless, table.borderless td, table.borderless th {
border: 0 }
table.borderless td, table.borderless th {
/* Override padding for "table.docutils td" with "! important".
The right padding separates the table cells. */
padding: 0 0.5em 0 0 ! important }
.first {
/* Override more specific margin styles with "! important". */
margin-top: 0 ! important }
.last, .with-subtitle {
margin-bottom: 0 ! important }
.hidden {
display: none }
a.toc-backref {
text-decoration: none ;
color: black }
blockquote.epigraph {
margin: 2em 5em ; }
dl.docutils dd {
margin-bottom: 0.5em }
/* Uncomment (and remove this text!) to get bold-faced definition list terms
dl.docutils dt {
font-weight: bold }
*/
div.abstract {
margin: 2em 5em }
div.abstract p.topic-title {
font-weight: bold ;
text-align: center }
div.admonition, div.attention, div.caution, div.danger, div.error,
div.hint, div.important, div.note, div.tip, div.warning {
margin: 2em ;
border: medium outset ;
padding: 1em }
div.admonition p.admonition-title, div.hint p.admonition-title,
div.important p.admonition-title, div.note p.admonition-title,
div.tip p.admonition-title {
font-weight: bold ;
font-family: sans-serif }
div.attention p.admonition-title, div.caution p.admonition-title,
div.danger p.admonition-title, div.error p.admonition-title,
div.warning p.admonition-title {
color: red ;
font-weight: bold ;
font-family: sans-serif }
/* Uncomment (and remove this text!) to get reduced vertical space in
compound paragraphs.
div.compound .compound-first, div.compound .compound-middle {
margin-bottom: 0.5em }
div.compound .compound-last, div.compound .compound-middle {
margin-top: 0.5em }
*/
div.dedication {
margin: 2em 5em ;
text-align: center ;
font-style: italic }
div.dedication p.topic-title {
font-weight: bold ;
font-style: normal }
div.figure {
margin-left: 2em ;
margin-right: 2em }
div.footer, div.header {
clear: both;
font-size: smaller }
div.line-block {
display: block ;
margin-top: 1em ;
margin-bottom: 1em }
div.line-block div.line-block {
margin-top: 0 ;
margin-bottom: 0 ;
margin-left: 1.5em }
div.sidebar {
margin: 0 0 0.5em 1em ;
border: medium outset ;
padding: 1em ;
background-color: #ffffee ;
width: 40% ;
float: right ;
clear: right }
div.sidebar p.rubric {
font-family: sans-serif ;
font-size: medium }
div.system-messages {
margin: 5em }
div.system-messages h1 {
color: red }
div.system-message {
border: medium outset ;
padding: 1em }
div.system-message p.system-message-title {
color: red ;
font-weight: bold }
div.topic {
margin: 2em }
h1.section-subtitle, h2.section-subtitle, h3.section-subtitle,
h4.section-subtitle, h5.section-subtitle, h6.section-subtitle {
margin-top: 0.4em }
h1.title {
text-align: center }
h2.subtitle {
text-align: center }
hr.docutils {
width: 75% }
img.align-left {
clear: left }
img.align-right {
clear: right }
ol.simple, ul.simple {
margin-bottom: 1em }
ol.arabic {
list-style: decimal }
ol.loweralpha {
list-style: lower-alpha }
ol.upperalpha {
list-style: upper-alpha }
ol.lowerroman {
list-style: lower-roman }
ol.upperroman {
list-style: upper-roman }
p.attribution {
text-align: right ;
margin-left: 50% }
p.caption {
font-style: italic }
p.credits {
font-style: italic ;
font-size: smaller }
p.label {
white-space: nowrap }
p.rubric {
font-weight: bold ;
font-size: larger ;
color: maroon ;
text-align: center }
p.sidebar-title {
font-family: sans-serif ;
font-weight: bold ;
font-size: larger }
p.sidebar-subtitle {
font-family: sans-serif ;
font-weight: bold }
p.topic-title {
font-weight: bold }
pre.address {
margin-bottom: 0 ;
margin-top: 0 ;
font-family: serif ;
font-size: 100% }
pre.literal-block, pre.doctest-block {
margin-left: 2em ;
margin-right: 2em }
span.classifier {
font-family: sans-serif ;
font-style: oblique }
span.classifier-delimiter {
font-family: sans-serif ;
font-weight: bold }
span.interpreted {
font-family: sans-serif }
span.option {
white-space: nowrap }
span.pre {
white-space: pre }
span.problematic {
color: red }
span.section-subtitle {
/* font-size relative to parent (h1..h6 element) */
font-size: 80% }
table.citation {
border-left: solid 1px gray;
margin-left: 1px }
table.docinfo {
margin: 2em 4em }
table.docutils {
margin-top: 0.5em ;
margin-bottom: 0.5em }
table.footnote {
border-left: solid 1px black;
margin-left: 1px }
table.docutils td, table.docutils th,
table.docinfo td, table.docinfo th {
padding-left: 0.5em ;
padding-right: 0.5em ;
vertical-align: top }
table.docutils th.field-name, table.docinfo th.docinfo-name {
font-weight: bold ;
text-align: left ;
white-space: nowrap ;
padding-left: 0 }
h1 tt.docutils, h2 tt.docutils, h3 tt.docutils,
h4 tt.docutils, h5 tt.docutils, h6 tt.docutils {
font-size: 100% }
ul.auto-toc {
list-style-type: none }
</style>
</head>
<body>
<div class="document" id="history-mpi-for-python">
<h1 class="title">HISTORY: MPI for Python</h1>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Author:</th>
<td>Lisandro Dalcin</td></tr>
<tr><th class="docinfo-name">Contact:</th>
<td><a class="first last reference external" href="mailto:dalcinl%40gmail.com">dalcinl<span>@</span>gmail<span>.</span>com</a></td></tr>
<tr class="field"><th class="docinfo-name">Web Site:</th><td class="field-body"><a class="reference external" href="http://mpi4py.googlecode.com/">http://mpi4py.googlecode.com/</a></td>
</tr>
<tr><th class="docinfo-name">Organization:</th>
<td>CIMEC <<a class="reference external" href="http://www.cimec.org.ar">http://www.cimec.org.ar</a>></td></tr>
<tr><th class="docinfo-name">Address:</th>
<td><pre class="address">
CCT CONICET, 3000 Santa Fe, Argentina
</pre>
</td></tr>
</tbody>
</table>
<div class="section" id="release-1-2-2-2010-09-13">
<h1>Release 1.2.2 [2010-09-13]</h1>
<ul>
<li><p class="first">Add <tt class="docutils literal"><span class="pre">mpi4py.get_config()</span></tt> to retrieve information (compiler
wrappers, includes, libraries, etc) about the MPI implementation
employed to build mpi4py.</p>
</li>
<li><p class="first">Workaround Python libraries with missing GILState-related API calls
in case of non-threaded Python builds.</p>
</li>
<li><p class="first">Windows: look for MPICH2, DeinoMPI, Microsoft HPC Pack at their
default install locations under %ProgramFiles.</p>
</li>
<li><p class="first">MPE: fix hacks related to old API's, these hacks are broken when MPE
is built with a MPI implementations other than MPICH2.</p>
</li>
<li><p class="first">HP-MPI: fix for missing Fortran datatypes, use dlopen() to load the
MPI shared library before MPI_Init()</p>
</li>
<li><p class="first">Many distutils-related fixes, cleanup, and enhancements, better
logics to find MPI compiler wrappers.</p>
</li>
<li><p class="first">Support for <tt class="docutils literal"><span class="pre">pip</span> <span class="pre">install</span> <span class="pre">mpi4py</span></tt>.</p>
</li>
</ul>
</div>
<div class="section" id="release-1-2-1-2010-02-26">
<h1>Release 1.2.1 [2010-02-26]</h1>
<ul>
<li><p class="first">Fix declaration in Cython include file. This declaration, while
valid for Cython, broke the simple-minded parsing used in
conf/mpidistutils.py to implement configure-tests for availability
of MPI symbols.</p>
</li>
<li><p class="first">Update SWIG support and make it compatible with Python 3. Also
generate an warning for SWIG < 1.3.28.</p>
</li>
<li><p class="first">Fix distutils-related issues in Mac OS X. Now ARCHFLAGS environment
variable is honored of all Python's <tt class="docutils literal"><span class="pre">config/Makefile</span></tt> variables.</p>
</li>
<li><p class="first">Fix issues with Open MPI < 1.4.2 releated to error checking and
<tt class="docutils literal"><span class="pre">MPI_XXX_NULL</span></tt> handles.</p>
</li>
</ul>
</div>
<div class="section" id="release-1-2-2009-12-29">
<h1>Release 1.2 [2009-12-29]</h1>
<ul>
<li><p class="first">Automatic MPI datatype discovery for NumPy arrays and PEP-3118
buffers. Now buffer-like objects can be messaged directly, it is no
longer required to explicitly pass a 2/3-list/tuple like <tt class="docutils literal"><span class="pre">[data,</span>
<span class="pre">MPI.DOUBLE]</span></tt>, or <tt class="docutils literal"><span class="pre">[data,</span> <span class="pre">count,</span> <span class="pre">MPI.DOUBLE]</span></tt>. Only basic types
are supported, i.e., all C/C99-native signed/unsigned integral types
and single/double precision real/complex floating types. Many thanks
to Eilif Muller for the initial feedback.</p>
</li>
<li><p class="first">Nonblocking send of pickled Python objects. Many thanks to Andreas
Kloeckner for the initial patch and enlightening discussion about
this enhancement.</p>
</li>
<li><p class="first"><tt class="docutils literal"><span class="pre">Request</span></tt> instances now hold a reference to the Python object
exposing the buffer involved in point-to-point communication or
parallel I/O. Many thanks to Andreas Kloeckner for the initial
feedback.</p>
</li>
<li><p class="first">Support for logging of user-defined states and events using <a class="reference external" href="http://www.mcs.anl.gov/research/projects/perfvis/">MPE</a>. Runtime
(i.e., without requiring a recompile!) activation of logging of all
MPI calls is supported in POSIX platforms implementing <tt class="docutils literal"><span class="pre">dlopen()</span></tt>.</p>
</li>
<li><p class="first">Support for all the new features in MPI-2.2 (new C99 and F90
datatypes, distributed graph topology, local reduction operation,
and other minor enhancements).</p>
</li>
<li><p class="first">Fix the annoying issues related to Open MPI and Python dynamic
loading of extension modules in platforms supporting <tt class="docutils literal"><span class="pre">dlopen()</span></tt>.</p>
</li>
<li><p class="first">Fix SLURM dynamic loading issues on SiCortex. Many thanks to Ian
Langmore for providing me shell access.</p>
</li>
</ul>
</div>
<div class="section" id="release-1-1-0-2009-06-06">
<h1>Release 1.1.0 [2009-06-06]</h1>
<ul>
<li><p class="first">Fix bug in <tt class="docutils literal"><span class="pre">Comm.Iprobe()</span></tt> that caused segfaults as Python C-API
calls were issued with the GIL released (issue #2).</p>
</li>
<li><p class="first">Add <tt class="docutils literal"><span class="pre">Comm.bsend()</span></tt> and <tt class="docutils literal"><span class="pre">Comm.ssend()</span></tt> for buffered and
synchronous send semantics when communicating general Python
objects.</p>
</li>
<li><p class="first">Now the call <tt class="docutils literal"><span class="pre">Info.Get(key)</span></tt> return a <em>single</em> value (i.e, instead
of a 2-tuple); this value is <tt class="docutils literal"><span class="pre">None</span></tt> if <tt class="docutils literal"><span class="pre">key</span></tt> is not in the
<tt class="docutils literal"><span class="pre">Info</span></tt> object, or a string otherwise. Previously, the call
redundantly returned <tt class="docutils literal"><span class="pre">(None,</span> <span class="pre">False)</span></tt> for missing key-value pairs;
<tt class="docutils literal"><span class="pre">None</span></tt> is enough to signal a missing entry.</p>
</li>
<li><p class="first">Add support for parametrized Fortran datatypes.</p>
</li>
<li><p class="first">Add support for decoding user-defined datatypes.</p>
</li>
<li><p class="first">Add support for user-defined reduction operations on memory
buffers. However, at most 16 user-defined reduction operations
can be created. Ask the author for more room if you need it.</p>
</li>
</ul>
</div>
<div class="section" id="release-1-0-0-2009-03-20">
<h1>Release 1.0.0 [2009-03-20]</h1>
<p>This is the fist release of the all-new, Cython-based, implementation
of <em>MPI for Python</em>. Unfortunately, this implementation is not
backward-compatible with the previous one. The list below summarizes
the more important changes that can impact user codes.</p>
<ul>
<li><p class="first">Some communication calls had <em>overloaded</em> functionality. Now there
is a clear distinction between communication of general Python
object with <em>pickle</em>, and (fast, near C-speed) communication of
buffer-like objects (e.g., NumPy arrays).</p>
<ul>
<li><p class="first">for communicating general Python objects, you have to use
all-lowercase methods, like <tt class="docutils literal"><span class="pre">send()</span></tt>, <tt class="docutils literal"><span class="pre">recv()</span></tt>, <tt class="docutils literal"><span class="pre">bcast()</span></tt>,
etc.</p>
</li>
<li><p class="first">for communicating array data, you have to use <tt class="docutils literal"><span class="pre">Send()</span></tt>,
<tt class="docutils literal"><span class="pre">Recv()</span></tt>, <tt class="docutils literal"><span class="pre">Bcast()</span></tt>, etc. methods. Buffer arguments to these
calls must be explicitly specified by using a 2/3-list/tuple like
<tt class="docutils literal"><span class="pre">[data,</span> <span class="pre">MPI.DOUBLE]</span></tt>, or <tt class="docutils literal"><span class="pre">[data,</span> <span class="pre">count,</span> <span class="pre">MPI.DOUBLE]</span></tt> (the
former one uses the byte-size of <tt class="docutils literal"><span class="pre">data</span></tt> and the extent of the
MPI datatype to define the <tt class="docutils literal"><span class="pre">count</span></tt>).</p>
</li>
</ul>
</li>
<li><p class="first">Indexing a communicator with an integer returned a special object
associating the communication with a target rank, alleviating you
from specifying source/destination/root arguments in point-to-point
and collective communications. This functionality is no longer
available, expressions like:</p>
<pre class="literal-block">
MPI.COMM_WORLD[0].Send(...)
MPI.COMM_WORLD[0].Recv(...)
MPI.COMM_WORLD[0].Bcast(...)
</pre>
<p>have to be replaced by:</p>
<pre class="literal-block">
MPI.COMM_WORLD.Send(..., dest=0)
MPI.COMM_WORLD.Recv(..., source=0)
MPI.COMM_WORLD.Bcast(..., root=0)
</pre>
</li>
<li><p class="first">Automatic MPI initialization (i.e., at import time) requests the
maximum level of MPI thread support (i.e., it is done by calling
<tt class="docutils literal"><span class="pre">MPI_Init_thread()</span></tt> and passing <tt class="docutils literal"><span class="pre">MPI_THREAD_MULTIPLE</span></tt>). In case
you need to change this behavior, you can tweak the contents of the
<tt class="docutils literal"><span class="pre">mpi4py.rc</span></tt> module.</p>
</li>
<li><p class="first">In order to obtain the values of predefined attributes attached to
the world communicator, now you have to use the <tt class="docutils literal"><span class="pre">Get_attr()</span></tt>
method on the <tt class="docutils literal"><span class="pre">MPI.COMM_WORLD</span></tt> instance:</p>
<pre class="literal-block">
tag_ub = MPI.COMM_WORLD.Get_attr(MPI.TAG_UB)
</pre>
</li>
<li><p class="first">In the previous implementation, <tt class="docutils literal"><span class="pre">MPI.COMM_WORLD</span></tt> and
<tt class="docutils literal"><span class="pre">MPI.COMM_SELF</span></tt> were associated to <strong>duplicates</strong> of the (C-level)
<tt class="docutils literal"><span class="pre">MPI_COMM_WORLD</span></tt> and <tt class="docutils literal"><span class="pre">MPI_COMM_SELF</span></tt> predefined communicator
handles. Now this is no longer the case, <tt class="docutils literal"><span class="pre">MPI.COMM_WORLD</span></tt> and
<tt class="docutils literal"><span class="pre">MPI.COMM_SELF</span></tt> proxies the <strong>actual</strong> <tt class="docutils literal"><span class="pre">MPI_COMM_WORLD</span></tt> and
<tt class="docutils literal"><span class="pre">MPI_COMM_SELF</span></tt> handles.</p>
</li>
<li><p class="first">Convenience aliases <tt class="docutils literal"><span class="pre">MPI.WORLD</span></tt> and <tt class="docutils literal"><span class="pre">MPI.SELF</span></tt> were removed. Use
instead <tt class="docutils literal"><span class="pre">MPI.COMM_WORLD</span></tt> and <tt class="docutils literal"><span class="pre">MPI.COMM_SELF</span></tt>.</p>
</li>
<li><p class="first">Convenience constants <tt class="docutils literal"><span class="pre">MPI.WORLD_SIZE</span></tt> and <tt class="docutils literal"><span class="pre">MPI.WORLD_RANK</span></tt> were
removed. Use instead <tt class="docutils literal"><span class="pre">MPI.COMM_WORLD.Get_size()</span></tt> and
<tt class="docutils literal"><span class="pre">MPI.COMM_WORLD.Get_rank()</span></tt>.</p>
</li>
</ul>
</div>
</div>
</body>
</html>
