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<span id="label-heterogeneous-mpi-apps"></span><h1><span class="section-number">11.12. </span>Building heterogeneous MPI applications<a class="headerlink" href="#building-heterogeneous-mpi-applications" title="Permalink to this heading"></a></h1>
<p>Heterogeneous support (specifically: supporting different sized and/or
represented data types in a single MPI application run) within a
single MPI job is technically required by the MPI standard.</p>
<p>However, there are both theoretical and practical problems with
supporting true data heterogeneity at run-time.</p>
<p>Indeed, it is quite uncommon for production HPC environments to be
data-heterogeneous (e.g., natively support little-endian on some nodes
and big-endian on other nodes in the same MPI application job).</p>
<p>As such, supporting data heterogeneity is a feature that has fallen
into disrepair and is currently known to be broken in this release of
Open MPI.</p>
<p><a class="reference internal" href="../contributing.html"><span class="doc">Contributions to fix it would be welcome!</span></a></p>
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