I am not sure what you are talking about. wrk2 can put out 7M req/s on a 16 core box. That is way beyond Phoenix's performance on the same HW type. wrk2 is widely used and accepted performance measurement tool. Again, you mentioned microseconds latency which means you are talking about localhost microbenchmarking. That is irrelevant from the production workload point of view. I have saturated network links successfully with wrk2 which is the definition of fast enough.
Interestingly there was a thread on HN previously which tools are used for HTTP perf testing:
>>> - Wrk: https://github.com/wg/wrk - Fastest tool in the universe. About 25x faster than Locust. 3x faster than Jmeter. Scriptable in Lua. Drawbacks are limited output options/reporting and a scripting API that is callback-based, so painful to use for scripting user scenario flows.
alright. this looks interesting. I'll have to dive back into this space and see what's changed, I'm probably out of the loop. What's the diff between "wrk" and "wrk2"?
The only measuring tool that is fast enough to accurately measure Phoenix performance is something like Tsung (which is also an Erlang app...)