@Override
    public void calculate() {
        setValue(this.total / getDurationInMinute());
    }
@Test
    public void testCalculate() {
        long time1 = 1597113318673L;
        long time2 = 1597113447737L;
        function.accept(MeterEntity.newService("sum_sync_time", Layer.GENERAL), time1);
        function.accept(MeterEntity.newService("sum_sync_time", Layer.GENERAL), time2);
        function.calculate();
        assertThat(function.getValue()).isEqualTo(time1 + time2);
    }