Collectives

Non-blocking NCCL’s basic collectives (apart from reduce-scatter). The execution space and communication space handle have the same behavior as the P2P functions.

template <
  KokkosView View,
  KokkosExecutionSpace ExecSpace,
  CommunicationSpace CommSpace
>
auto broadcast(
  ExecSpace const& exec,
  Handle<CommSpace> const& handle,
  View view,
  RankId root
) -> std::expected<Request, Error>;

template <
  KokkosViewIn ViewIn,
  KokkosViewOut ViewOut,
  KokkosExecutionSpace ExecSpace,
  CommunicationSpace CommSpace
>
auto reduce(
  ExecSpace const& exec,
  Handle<CommSpace> const& handle,
  ViewIn input,
  ViewOut output,
  ReduceOp op,
  RankId root
) -> std::expected<Request, Error>;

template <
  KokkosViewIn ViewIn,
  KokkosViewOut ViewOut,
  KokkosExecutionSpace ExecSpace,
  CommunicationSpace CommSpace
>
auto all_reduce(
  ExecSpace const& exec,
  Handle<CommSpace> const& handle,
  ViewIn input,
  ViewOut output,
  ReduceOp op
) -> std::expected<Request, Error>;

template <
  KokkosViewIn ViewIn,
  KokkosViewOut ViewOut,
  KokkosExecutionSpace ExecSpace,
  CommunicationSpace CommSpace
>
auto all_gather(
  ExecSpace const& exec,
  Handle<CommSpace> const& handle,
  ViewIn input,
  ViewOut output,
) -> std::expected<Request, Error>;

template <
  KokkosViewIn ViewIn,
  KokkosViewOut ViewOut,
  KokkosExecutionSpace ExecSpace,
  CommunicationSpace CommSpace
>
auto all_to_all(
  ExecSpace const& exec,
  Handle<CommSpace> const& handle,
  ViewIn input,
  ViewOut output
) -> std::expected<Request, Error>;