可以根据核函数执行时间与矩阵 A, B 的大小, 推算出有效显存带宽 // 数据传输的字节数(写 + 读) / 执行时间 // 在 copy 例子中, 因为是合并访问, 所以有效显存带宽为 2 * N * N / T __global__ void copy(const real *A, real *B, const int N) { // 核函数...
cudaMemcpy(dev_ptr, &host_data, sizeof(float), cudaMemcpyHostToDevice); printf("host, copy %.2f to global variable\n", host_data); AddGlobalVariable<<<1, 1>>>(); cudaMemcpy(&host_data, dev_ptr, sizeof(float), cudaMemcpyDeviceToHost); printf("host, get %.2f from global variabl...
CUDA的数据拷贝以及核函数都有专门的stream参数来接收流,以告知该操作放入哪个流中执行: numba.cuda.to_device(obj, stream=0, copy=True, to=None) numba.cuda.copy_to_host(self, ary=None, stream=0) 核函数调用的地方除了要写清执行配置,还要加一项stream参数: kernel[blocks_per_grid, threads_per_bloc...
Copy __device__ float3 bodyBodyInteraction(float4 bi, float4 bj, float3 ai) { float3 r; // r_ij [3 FLOPS] r.x = bj.x - bi.x; r.y = bj.y - bi.y; r.z = bj.z - bi.z; // distSqr = dot(r_ij, r_ij) + EPS^2 [6 FLOPS] float distSqr = r.x * ...
if (threadIdx.x == 0) { child_launch<<< 1, 256 >>>(data); cudaDeviceSynchronize(); } __syncthreads(); } void host_launch(int *data) { parent_launch<<< 1, 256 >>>(data); } D.2.2.1.2. Zero Copy Memory 零拷贝系统内存与全局内存具有相同的一致性和一致性保证,并遵循上面详述的语...
copy_to_host() if __name__ == "__main__": main() 进行Shared Memory优化后,计算部分的耗时减少了近一半: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 matmul time :1.4370720386505127 matmul with shared memory time :0.7994928359985352 补充说明 声明Shared Memory。这里使用了cuda.shared.array(...
1//Copy data from host to device2cudaMemcpy(device_data, host_data, size, cudaMemcpyHostToDevice);34//Copy data from device to host5cudaMemcpy(host_data, device_data, size, cudaMemcpyDeviceToHost); 以上代码分别演示了如何从主机内存复制数据到设备内存,以及如何从设备内存复制数据到主机内存。CUDA...
nvdisasm is capable of showing line number information with additional function inlining info (if any). In absence of any function inlining the output is same as the one with nvdisasm -g command. Here’s a sample output of a kernel using nvdisasm -gi command: //--- .text._Z6kernali...
(int)*m*k)); // copy matrix A and B from host to device memory CHECK(cudaMemcpy(d_a, h_a, sizeof(int)*m*n, cudaMemcpyHostToDevice)); CHECK(cudaMemcpy(d_b, h_b, sizeof(int)*n*k, cudaMemcpyHostToDevice)); unsigned int grid_rows = (m + BLOCK_SIZE - 1) / BLOCK_SIZE...
If the memory region refers to valid system-allocated pageable memory, then the accessing device must have a non-zero value for the device attribute cudaDevAttrPageableMemoryAccess for a read-only copy to be created on that device. Note however that if the accessing device also has a non-...