public ProgressLoggers addFileSize(DiskBacked longSupplier) {
    return add(() -> " " + padRight(format.storage(longSupplier.diskUsageBytes(), false), 5));
  }
Adds the current number of items in a queue and the queue's size to the output.
planetiler-core/src/main/java/com/onthegomap/planetiler/stats/ProgressLoggers.java