-1
當我打電話給curand時,我總是在一個線程中得到相同的數字。但是,它們對於每個線程都不相同。我在下一個代碼中做錯了什麼?curand每次在一個線程中給出相同的數字
#define MAXTHREADS 2
#define NBBLOCKS 2
__global__ void testRand (curandState * state, int nb){
int id = threadIdx.x + blockIdx.x * blockDim.x;
int value;
for (int i=0;i<nb;i++){
curandState localState = state[id];
value = curand(&localState);
printf("Id %i, value %i\n",id,value);
}
}
__global__ void setup_kernel (curandState * state, unsigned long seed)
{
int id = threadIdx.x + blockIdx.x * blockDim.x;
curand_init (seed, id , 0, &state[id]);
}
/**
* Image comes in in horizontal lines
*/
void findOptimum() {
const dim3 blockSize(MAXTHREADS);
const dim3 gridSize(NBBLOCKS);
curandState* devStates;
cudaMalloc (&devStates,MAXTHREADS*NBBLOCKS*sizeof(curandState));
time_t t;
time(&t);
setup_kernel <<< gridSize, blockSize >>> (devStates, (unsigned long) t);
int nb = 4;
testRand <<< gridSize, blockSize >>> (devStates,nb);
testRand <<< gridSize, blockSize >>> (devStates,nb);
cudaFree(devStates);
}
它輸出:
Id 0, value -1075808309
Id 1, value -1660353324
Id 2, value 1282291714
Id 3, value -1892750252
Id 0, value -1075808309
Id 1, value -1660353324
Id 2, value 1282291714
Id 3, value -1892750252
...
這重複了幾次。
您從不修改全局內存生成器狀態。你期望會發生什麼? – talonmies
好的,謝謝! 我認爲它是自動完成的,但由於我沒有通過任何參考全球國家,這是不可能的課程。 – Curantil