bench.sh

#!/bin/sh

for port in $(seq 3000 3003); do
  echo $port

  for c in 1 3 5 10 20; do
    echo "Concurrency: ${c}"

    for i in $(seq 1 3); do
      ab -n 100 -c ${c} localhost:${port}/ 2> /dev/null | grep 'per second'
    done
  done
done

config.ru

body = ['a' * 1024 * 512]

run ->(env) {
  sleep 0.05 # simulate blocking I/O

  [200, {}, body]
}

Gemfile

gem 'foreman'
gem 'puma'
gem 'rainbows'
gem 'sendfile'
gem 'sleepy_penguin'
gem 'thin'
gem 'unicorn'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    daemons (1.1.9)
    eventmachine (1.0.1)
    foreman (0.61.0)
      thor (>= 0.13.6)
    kgio (2.8.0)
    puma (1.6.3)
      rack (~> 1.2)
    rack (1.5.2)
    rainbows (4.5.0)
      kgio (~> 2.5)
      rack (~> 1.1)
      unicorn (~> 4.6, >= 4.6.2)
    raindrops (0.10.0)
    sendfile (1.1.0)
    sleepy_penguin (3.1.0)
    thin (1.5.0)
      daemons (>= 1.0.9)
      eventmachine (>= 0.12.6)
      rack (>= 1.0.0)
    thor (0.17.0)
    unicorn (4.6.2)
      kgio (~> 2.6)
      rack
      raindrops (~> 0.7)

PLATFORMS
  ruby

DEPENDENCIES
  foreman
  puma
  rainbows
  sendfile
  sleepy_penguin
  thin
  unicorn

Procfile

thin:     bundle exec thin start -p 3000
unicorn:  bundle exec unicorn -c unicorn.conf -p 3001
rainbows: bundle exec rainbows -c rainbows.conf -p 3002
puma:     bundle exec puma -t 5:5 -p 3003

rainbows.conf

worker_processes 5

Rainbows! do
  use :Epoll
end

unicorn.conf

worker_processes 5