Ruby on Rails performance on EC2 large instance

Hi,

I’ve tried to install and run the benchmark script
at GitHub - TechEmpower/FrameworkBenchmarks: Source for the TechEmpower Framework Benchmarks project but I never got as
much performance as it stated on the website
at
TechEmpower Framework Benchmarks

The peak performance we got is around 450 requests/second. The result
from
them is 750 requests/second.

Could someone help us? I think we may did some mis-configuration.

Thank you!