stack_level_too_deep.rb

#!/usr/bin/env ruby

class Infinity
  def self.run
    1.times { run }
  end
end

Thread.new do
  loop do
    begin
      puts "T1: Start infinity"
      Infinity.run
    rescue Exception => e
      puts "T1: #{e.message}"
    end
    puts "T1: Sleep infinity"
    sleep 3
  end
end

7.times do
  GC.start
  puts "GC major: #{GC.stat[:major_gc_count]}, minor: #{GC.stat[:minor_gc_count]}, threads: #{Thread.list.size}"
  sleep 1
end

puts "Done."

# $ ruby -v
# ruby 2.3.0dev (2015-11-19 trunk 52668) [x86_64-darwin15]
#
# T1: Start infinity
# GC major: 1, minor: 0, threads: 2
# T1: stack level too deep
# T1: Sleep infinity
# GC major: 2, minor: 0, threads: 2
# GC major: 3, minor: 0, threads: 2
# T1: Start infinity
#
# $ ps aux | grep -E '[R]SS|[r]uby'
# USER              PID  %CPU %MEM      VSZ    RSS   TT  STAT STARTED      TIME COMMAND
# ebeigarts       27301  58.2  0.6  2511120  48596 s006  R+   10:46AM   1:04.51 ruby ./gc_threads_issue.rb
#
# $ kill 27301
# $ sleep 60
#
# $ ps aux | grep -E '[R]SS|[r]uby'
# USER              PID  %CPU %MEM      VSZ    RSS   TT  STAT STARTED      TIME COMMAND
# ebeigarts       27301  55.9  0.6  2511120  48596 s006  S+   10:46AM   2:10.72 ruby ./gc_threads_issue.rb