Benchmarking Ruby performance in Docker Containers

.gitignore

/*.log

build.sh

#! /usr/bin/env bash

set -o errexit
set -o nounset

for tag in alpine ubuntu ruby
do
    docker build -t ruby_performance:${tag} -f Dockerfile.${tag} .
done

cpuram.rb

#! /usr/bin/env ruby

require "benchmark/ips"

def recursive(n)
  return 1 if n < 2
  recursive(n-1) + recursive(n-2)
end

def iter(n)
  a, b = 1, 1

  n.times { a, b = b, a+b }

  a
end

N = Integer(ARGV.first || 100)

puts "Calculating Fibonacci(#{N})"

Benchmark.ips do |r|
  r.report("recursive") { recursive(N) }
  r.report("iterative") { iter(N) }
  r.compare!
end

Dockerfile.alpine

FROM alpine:3.2
RUN apk add --update ruby ruby-json \
    && gem install --no-document benchmark-ips
ADD *.rb /tmp/
LABEL com.citrusbyte.bits.article=ruby-docker-performance
ENTRYPOINT ["ruby"]
CMD ["/tmp/benchmark.rb"]

Dockerfile.ruby

FROM ruby:2.2
RUN gem install --no-ri --no-rdoc benchmark-ips
ADD *.rb /tmp/
LABEL com.citrusbyte.bits.article=ruby-docker-performance
ENTRYPOINT ["ruby"]
CMD ["/tmp/benchmark.rb"]

Dockerfile.ubuntu

FROM ubuntu:14.04
RUN apt-get upgrade -y \
    && apt-get install -y ruby2.0 \
    && gem2.0 install --no-ri --no-rdoc benchmark-ips
ADD *.rb /tmp/
LABEL com.citrusbyte.bits.article=ruby-docker-performance
ENTRYPOINT ["ruby2.0"]
CMD ["/tmp/benchmark.rb"]

performance.rb

#! /usr/bin/env ruby

require "json"
require "time"
require "benchmark/ips"

NOW     = Time.now
ISO8601 = NOW.iso8601
PAYLOAD = { timestamp: "2015-08-12T18:17:22-03:00", values: { humidity: 80, temperature: 23 } }

Benchmark.ips do |r|
  r.report("JSON.dump") { JSON.dump(PAYLOAD) }

  payload = JSON.dump(PAYLOAD)
  r.report("JSON.parse") { JSON.parse(payload) }

  r.report("Time#iso8601") { NOW.iso8601 }
  r.report("Time.iso8601") { Time.iso8601(ISO8601) }
end

run.sh

#! /usr/bin/env bash

set -o errexit

if [[ -z $1 ]]
then
    echo "Usage: ${0} <peformance|cpuram>"
    exit 1
fi

set -o nounset

test=$1

shift

for tag in alpine ubuntu ruby
do
    echo "Executing ${test}.rb in ruby_performance:${tag}"
    docker run --rm ruby_performance:${tag} /tmp/${test}.rb $@ | tee ${tag}.${test}.log
    echo
done