Random curand在线程中每次都给出相同的数字

Random curand在线程中每次都给出相同的数字,random,cuda,Random,Cuda,当我打电话给curand时,我总是在一个线程中得到相同的号码。但是,每种线程都不同。在下一个代码中我做错了什么 #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

当我打电话给curand时,我总是在一个线程中得到相同的号码。但是,每种线程都不同。在下一个代码中我做错了什么

#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);
}

这会重复几次。

正如Talonmes指出的,我没有修改全局状态


使用
curand(localState)
在te行之后添加
state[id]=localState
修复了该问题。

您永远不会修改全局内存生成器或状态。你认为会发生什么?好的,谢谢!我假设它是自动完成的,但由于我没有传递任何对全局状态的引用,这是不可能的。
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
...