I don’t know the exact details of the test that was run for this, though someone else here may. I can say, though, that the test used our built-in performance testing capabilities. Evan posted a summary for how to use them in this forum post. The test that was run in the scaling benchmark was probably the RandomReadWrite test linked to by Evan, but with some different parameters. If you go this route, you’ll want to make sure to have sufficient clients (i.e. the test class processes) to saturate the cluster if you’re trying to get a sense for cluster throughput.