I found a piece of code in one example–EstimatePiQ in CUDA SDK:
computeValue<<<grid, block, block.x * sizeof(unsigned int)>>>(d_results, d_points, m_numSims);
About this kernel call, I know the first parameter grid specify the amount of grids and the second one block indicate the amount of blocks. But what’s the third parameter block.x * sizeof(unsigned int) used for??