supports a wide variety of operating systems and platforms; see the
opal/mca/paffinity/hwloc/hwloc/README file for details.
This component includes an embedded copy of hwloc, currently based on
hwloc-1.0rc6. But note that hwloc is properly SVN imported into the
/vendor branch, so it will be easy to update when 1.0 GA is released.
Note that the hwloc tree embedded in opal/mca/paffinity/hwloc/hwloc is
identical to a hwloc distribution tarball, except that much of the
documentation was rm -rf'ed (because we don't need it for the embedded
case).
Since the paffinity framework currently does not understand hardware
threads, the hwloc component compensates for this by identifying cores
by the "first" hardware thread on that core. Hopefully we'll update
paffinity someday to understand hardware threads. :-)
configure grew a --with-hwloc option, analogous to what we do for many
other external libraries that OMPI supports. However, there's a new
feature: due to the request of several distros, OMPI can be configured
to build with its internal copy of hwloc or with an external copy of
hwloc (e.g., a system-installed hwloc).
1. If --with-hwloc is not specified, Open MPI will try to use its
internal copy (but silently fail/ignore hwloc if that fails).
1. If --with-hwloc=<dir> is supplied, Open MPI looks for hwloc
support in <dir> (and --with-hwloc-libdir=<dir>, if specified).
1. If --with-hwloc=external is supplied, Open MPI will look for hwloc
in a compiler/linker default external location.
1. If --with-hwloc=internal is supplied, Open MPI will use its
internal copy of hwloc.
Some of OMPI's main configury had to be slightly re-arranged in the
bootstrapping phase to accomodate hwloc's configry needs.
This commit was SVN r23125.
3129ccd9ec