[resteasy-dev] Performance issues with async/CompletionStage/RxJava

Hi, I was doing some benchmarks with gatling and came across very strange results where if I have a REST endpoint with normal result types I get 1200 requests per second, but if I return those results inside RxJava's Single (with Single.just()) I get about 250 requests per second, and if I change that with CompletionStage (using CompletableFuture.completedFuture()) I get about 310 requests per second. Frankly I'm not sure how to go about finding out why we have such a difference, and whether we can mitigate it, but we should definitely try. How do you usually tackle these problems? Any help? Thanks, cheers.