code: @Override
      public double getValue() {
          final Runtime runtime = Runtime.getRuntime();
          memAlreadyUsed = memAlreadyUsed + runtime.totalMemory() - runtime.freeMemory();
          return new BigDecimal(memAlreadyUsed, MathContext.DECIMAL128).divide(new BigDecimal(scale.getNumberOfBytes()), MathContext.DECIMAL128).doubleValue();
      }
docs: {@inheritDoc}