interval_squelch.rb

class IntervalSquelch
  # Accepts an `interval` in fractional seconds and a `max_runs` as an integer.
  # Will ensure that `go` calls its block no more than `max_runs` times per
  # `interval`.
  #
  # By default, `max_runs` is 1.
  def initialize(interval, max_runs = 1)
    @max_runs = max_runs.to_i
    @interval = interval.to_f

    @tick = 0
    @runs = 0

    @start = Time.now.to_f
  end

  # `blk` will only be called if the number of times it's been called in this
  # interval does not exceed the maximum number of calls per interval.
  #
  # Returns `true` when the block was run; otherwise, returns `false`.
  def go(&blk)
    tick = ((Time.now.to_f - @start) / @interval).to_i

    if @tick != tick
      @tick = tick
      @runs = 0
    end

    unless @runs >= @max_runs
      blk.call()
      @runs += 1

      true
    else
      false
    end
  end
end

count = 0
start = Time.now.to_f

s = IntervalSquelch.new(0.5, 5)

loop do
  s.go do
    puts "Hello World :: %03d :: %0.05f" % [count, Time.now.to_f - start]
    count += 1
  end
end

$ruby interval_squelch.rb
Hello World :: 000 :: 0.00002
Hello World :: 001 :: 0.00005
Hello World :: 002 :: 0.00006
Hello World :: 003 :: 0.00007
Hello World :: 004 :: 0.00007
Hello World :: 005 :: 0.50002
Hello World :: 006 :: 0.50005
Hello World :: 007 :: 0.50006
Hello World :: 008 :: 0.50007
Hello World :: 009 :: 0.50007
Hello World :: 010 :: 1.00002
Hello World :: 011 :: 1.00006
Hello World :: 012 :: 1.00007
Hello World :: 013 :: 1.00008
Hello World :: 014 :: 1.00008