.ruby-version

2.3.5

Gemfile

# frozen_string_literal: true
source "https://rubygems.org"

gem 'get_process_mem'
gem 'rusage'
gem 'posix-spawn'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    get_process_mem (0.2.1)
    posix-spawn (0.3.13)
    rusage (0.2.0)

PLATFORMS
  ruby

DEPENDENCIES
  get_process_mem
  posix-spawn
  rusage

BUNDLED WITH
   1.16.0.pre.3

test.rb

# frozen_string_literal: true

require 'get_process_mem'
require 'rusage'
require 'benchmark'
# require 'posix/spawn'

memory_bloat = []
10_000.times { memory_bloat.push " "*10_000 }

n = 10_000
gpm = GetProcessMem.new

Benchmark.bm(10) do |x|
  x.report("status:") { n.times do gpm.linux_status_memory end }
  x.report("rusage:") { n.times do Process.rusage.maxrss end }
  # In sshaw version
  # x.report("statm:")  { n.times do gpm.linux_statm_memory end }
  # x.report("ps:") { n.times do `ps -o rss= -p #{$$}`.to_f end }
  # x.report("POSIX::Spawn:") { n.times do POSIX::Spawn.`("ps -o rss= -p #{$$}").to_f end }
end

puts "GetProcessMem: #{gpm.kb} kb"
puts "rusage:        #{Process.rusage.maxrss/1024.0} kb"
puts "ps:            #{`ps -o rss= -p #{$$}`.to_f} kb"
puts "oink:          #{`ps -o vsz= -p #{$$}`.to_f} kb" # this is what oink measures