Kokkos::fence

Kokkos::fence

Header File: Kokkos_Core.hpp

In general, kernels in Kokkos are running asynchronously and launching them returns immediately. This implies that its effects might not be visible to the calling thread. Kokkos::fence() guarantees that all parallel patterns in all execution spaces are guaranteed to have completed upon return and that any side-effects are visible. Effectively, calling Kokkos::fence() is equivalent to calling ExecutionSpace::fence() for all enabled execution spaces.

Usage: timing kernels

Kokkos::Timer timer;
// some kernel call, like Kokkos::parallel_for(...);
Kokkos::fence();
double time = timer.seconds();

using UVM

Kokkos::View<int*, Kokkos::CudaUVM> view("uvm_view", 10);
Kokkos::parallel_for(10, KOKKOS_LAMBDA (int n) { view(n) = n; });
Kokkos::fence();
for (unsigned int i=0; i<view.size(); ++i)
  std::cout << view(i) << std::endl;

Synopsis

void fence();

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