}
      writeln!(writer)?;

      if SHUTTING_DOWN.load(atomic::Ordering::Relaxed) {
        break;
      }
    }
    writer.flush()?;
    Ok(())
  }

  pub(crate) fn is_unrecoverably_reorged(&self) -> bool {
    self.unrecoverably_reorged.load(atomic::Ordering::Relaxed)
  }

  fn begin_read(&self) -> Result<rtx::Rtx> {
    Ok(rtx::Rtx(self.database.begin_read()?))
  }

  fn begin_write(&self) -> Result<WriteTransaction> {
    let mut tx = self.database.begin_write()?;
    tx.set_durability(self.durability);
    Ok(tx)
  }

  fn increment_statistic(wtx: &WriteTransaction, statistic: Statistic, n: u64) -> Result {
    let mut statistic_to_count = wtx.open_table(STATISTIC_TO_COUNT)?;
    let value = statistic_to_count
      .get(&(statistic.key()))?
      .map(|x| x.value())
      .unwrap_or(0)
      + n;
    statistic_to_count.insert(&statistic.key(), &value)?;
    Ok(())
  }

  #[cfg(test)]
  pub(crate) fn statistic(&self, statistic: Statistic) -> u64 {
    self
      .database
      .begin_read()
      .unwrap()