module Concurrent

def self.new_fast_executor(opts = {})
  FixedThreadPool.new(
      [2, Concurrent.processor_count].max,
      auto_terminate:  opts.fetch(:auto_terminate, true),
      idletime:        60, # 1 minute
      max_queue:       0, # unlimited
      fallback_policy: :abort, # shouldn't matter -- 0 max queue
      name:            "fast"
  )
end