Minor Description
GaussianRandomReadBenchmark generates seek keys by using a Gaussian distribution with the mean of N/2 and a sigma of N/10 (N = number of rows used) and using this key directly to seek into the HFile. The HFile was seeded with keys from 0-N.
This will fail if we ever generate a key < 0, which is rare, but by no means impossible. We need to clamp the min and max values to 0 and N, resp.