MPIContext

KokkosResilience::MPIContext

Context object using the MPI Backend

Header File: MPIContext.hpp

Synopsis

template <typename Backend>
class MPIContext : public ContextBase {
public:
explicit MPIContext(MPI_Comm comm, Config &cfg)
    : ContextBase(cfg), m_backend(*this, comm), m_comm(comm) {}

MPIContext(const MPIContext &) = delete;
MPIContext(MPIContext &&) noexcept = default;

MPIContext &operator=(const MPIContext &) = delete;
MPIContext &operator=(MPIContext &&) noexcept = default;

virtual ~MPIContext() {
#ifdef KR_ENABLE_TRACING
  int rank = -1;
  MPI_Comm_rank(m_comm, &rank);
  int size = -1;
  MPI_Comm_size(m_comm, &size);

  std::ostringstream fname;
  fname << "trace" << rank << ".json";

  std::ofstream out(fname.str());

  std::cout << "writing trace to " << fname.str() << '\n';

  trace().write(out);

  // Metafile
  picojson::object root;
  root["num_ranks"] = picojson::value(static_cast<double>(size));

  std::ofstream meta_out("meta.json");
  picojson::value(root).serialize(std::ostream_iterator<char>(meta_out),
                                  true);
#endif
}

MPI_Comm comm() const noexcept

Backend &backend()

void register_hashes(
    const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>> &views,
    const std::vector<Detail::CrefImpl> &crefs) override

bool restart_available(const std::string &label, int version) override 

void restart(const std::string &label, int version,
             const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>>
                 &views) override

void checkpoint(const std::string &label, int version,
                const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>>
                    &views) override 

int latest_version(const std::string &label) const noexcept override 

void register_alias( const std::string &original, const std::string &alias ) override 

void reset() override

Public Class Members

Constructors

• explicit MPIContext(MPI_Comm comm, Config &cfg)
      : ContextBase(cfg), m_backend(*this, comm), m_comm(comm) {}

  Construct a MPIContext with the supplied communicator and Config object.

• MPIContext(const MPIContext &) = delete;

  Copy constructor is deleted.

• MPIContext(MPIContext &&) noexcept = default;

  Move constructor.

Operators

• MPIContext &operator=(const MPIContext &) = delete;

  Copy constructor is deleted.

• MPIContext &operator=(MPIContext &&) noexcept = default;

  Move constructor.

Functions

• MPI_Comm comm() const noexcept

  Access the underlying communicator.

• Backend &backend()

  Access the underlying Backend. Returns a reference.

• void register_hashes(
      const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>> &views,
      const std::vector<Detail::CrefImpl> &crefs) override

  Register Views. Overrides the ContextBase implementation.

• bool restart_available(const std::string &label, int version) override

  Check if an existing restart is available. Searches based on the supplied label. version determines the most recent version to search for. For example, setting version to 5 will search for any restart up to version 5. Setting version to 0 will search for the most recent restart.

• void restart(const std::string &label, int version,
               const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>>
                   &views) override

  Restart the specified Views from the checkpoint determined by the label and version.

• void checkpoint(const std::string &label, int version,
                  const std::vector<std::unique_ptr<Kokkos::ViewHolderBase>>
                      &views) override

  Create a checkpoint of the specified Views.

• int latest_version(const std::string &label) const noexcept override

  Get the latest version of the checkpoint with the name label.

• void register_alias( const std::string &original, const std::string &alias ) override

  Register a new alias.

• void reset() override

  Reset the context.