object CacheActor {
  case class FindValue(params: Params)

  trait Params {
    def cacheKey: String
  }

  // Thread pool used by findValueForSender()
  val FUTURE_POOL_SIZE = 25

  private lazy val findValueThreadPoolExecutor =
    new ThreadPoolExecutor(FUTURE_POOL_SIZE, FUTURE_POOL_SIZE,
                           1, TimeUnit.MINUTES,
                           new ArrayBlockingQueue(FUTURE_POOL_SIZE, true))

  implicit lazy val findValueExecutionContext: ExecutionContext =
    ExecutionContext.fromExecutor(findValueThreadPoolExecutor)
}