I'd also suggest that such a light test didn't really test either server. It's highly unlikely you'll be able to significantly load Nginx with only a single client making requests.
Also, you didn't publish any information on CPU/RAM utilization for each server under the same load. Even if you can't load the servers up enough to create a significant req/s difference you should definitely see a large difference in resource utilization at whatever load you are able to generate.
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I'd also suggest that such a light test didn't really test either server. It's highly unlikely you'll be able to significantly load Nginx with only a single client making requests.
Also, you didn't publish any information on CPU/RAM utilization for each server under the same load. Even if you can't load the servers up enough to create a significant req/s difference you should definitely see a large difference in resource utilization at whatever load you are able to generate.