Just discovered the CUDA GPU Occupancy Calculator spreadsheet that will help you increase the occupancy ratio of your applications.
Occupancy is defined as [active warps]/[maximum warps].
You will always want your device cores to be used to its fullest potential at all times, so this ratio is important when optimizing your applications.
Here is the spreadsheet link: https://developer.download.nvidia.com/compute/cuda/CUDA_Occupancy_calculator.xls
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