I have a puzzle about whether need to allocate memory on GPU when using cudaMallocManaged（）.Please answer，thank you！
If you study this introduction:
you should be able to answer the question for yourself.
sorry, just like as follow:
cudaHostAlloc((void **)&h_A, nBytes, cudaHostAllocMapped);
cudaHostGetDevicePointer((void **)&d_A, (void *)h_A, 0);
is this just need to allocate memory on cpu not on device?
cudaHostAlloc returns a pointer to host memory, but that pointer can also be used in device code. Device code can access it using a “zero-copy” mechanism. Furthermore, host data allocated this way can be used with cudaMemcpyAsync for overlap of copy and compute operations.
This has nothing to do with cudaMallocManaged
thank you ,i see