collectives

The collectives module exposes a set of distributed collective operations. Those can be used to exchange data between participating sites in a coordinated way. At this point the module exposes the following collective primitives:

• hpx::collectives::all_gather: receives a set of values from all participating sites.

• hpx::collectives::all_reduce: performs a reduction on data from each participating site to each participating site.

• hpx::collectives::all_to_all: each participating site provides its element of the data to collect while all participating sites receive the data from every other site.

• hpx::collectives::broadcast_to and hpx::collectives::broadcast_from: performs a broadcast operation from a root site to all participating sites.

• cpp:func:hpx::collectives::exclusive_scan

  performs an exclusive scan operation

  on a set of values received from all call sites operating on the given base name.

• hpx::collectives::gather_here and hpx::collectives::gather_there: gathers values from all participating sites.

• cpp:func:hpx::collectives::inclusive_scan

  performs an inclusive scan operation

  on a set of values received from all call sites operating on the given base name.

• hpx::collectives::reduce_here and hpx::collectives::reduce_there: performs a reduction on data from each participating site to a root site.

• hpx::collectives::scatter_to and hpx::collectives::scatter_from: receives an element of a set of values operating on the given base name.

• hpx::lcos::broadcast: performs a given action on all given global identifiers.

• hpx::distributed::barrier: distributed barrier.

• hpx::lcos::fold: performs a fold with a given action on all given global identifiers.

• hpx::distributed::latch: distributed latch.

• hpx::lcos::reduce: performs a reduction on data from each given global identifiers.

• hpx::lcos::spmd_block: performs the same operation on a local image while providing handles to the other images.

See the API reference of the module for more details.