// in time it was present somewhere int the map. This becomes increasingly unlikely as
    // CONTAINS_VALUE_RETRIES increases, though without locking it is theoretically possible.
    long now = ticker.read();
    Segment<K, V>[] segments = this.segments;
    long last = -1L;
    for (int i = 0; i < CONTAINS_VALUE_RETRIES; i++) {
      long sum = 0L;