CUDA crashing when I iterate too many times

Accelerated Computing CUDA CUDA Programming and Performance
1

I have a program that iterates a simple “add-one” function 100 times, using shared memory with

a total grid size of 1024*1024 variables. When I run the program, it crashes CUDA. Code is posted

in full, in case that helps; any ideas what’s going on?

As always, thanks in advance for any ideas.

[codebox]global void FILENAME(int *d_out, int *d_in, int nIterations)

{

extern __shared__ int s_data[];

int in  = blockDim.x*blockIdx.x + threadIdx.x;

for (int k=0; k<nIterations; ++k)

{

    s_data[in] = d_in[in];

    __syncthreads();

    d_out[in] = s_data[in] + 1;

int *temp = d_out;

    d_out = d_in;

    d_in = temp;

}

}

int main(int argc, char** argv)

{

int *HOST_Array;

int dimA = 1024*1024;

int nIterations = 100;

int i;

int *device_OUT, *device_IN;

int numThreadsPerBlock = 256;

int numBlocks = dimA / numThreadsPerBlock;

int sharedMemSize = numThreadsPerBlock * sizeof(int);

size_t memSize = numBlocks * numThreadsPerBlock * sizeof(int);



HOST_Array = (int *) malloc(memSize);

cudaMalloc((void **) &device_IN, memSize);

cudaMalloc((void **) &device_OUT, memSize);

cudaMemcpy(device_IN, HOST_Array, memSize, cudaMemcpyHostToDevice);

dim3 dimGrid(numBlocks);

dim3 dimBlock(numThreadsPerBlock);

FILENAME <<<dimGrid, dimBlock, sharedMemSize>>> (device_OUT, device_IN, nIterations);

cudaThreadSynchronize();

cudaMemcpy(HOST_Array, device_OUT, memSize, cudaMemcpyDeviceToHost);

cudaFree(device_IN);

cudaFree(device_OUT);

free(HOST_Array);

}

[/codebox]

2

You’re probably hitting the Vista TDR limit. Set TdrLevel to 0 as described below (or set TdrDelay to something very high):

[url=“http://www.microsoft.com/whdc/device/display/wddm_timeout.mspx”]http://www.microsoft.com/whdc/device/displ...dm_timeout.mspx[/url]

3

per Microsoft’s WHQL, Drivers are not allowed to leave the kernel. please fix.

4

Uh, what are you talking about and why do you think our driver does this?

5

I got the TDR working, but now Vista’s capping my (float) dataset at 192x192; it crashes whenever I exceed that size. I’m running a 9800 GX2, so hardware is most definitely not the problem.