ConcentratorBaseRealTime Property

Gets the most accurate time value that is available. If UseLocalClockAsRealTime = true, then this function will return UtcNow. Otherwise, this function will return the timestamp of the most recent measurement, or UtcNow if no measurement timestamps are within time deviation tolerances as specified by the LeadTime value.

Definition

Namespace: Gemstone.Timeseries
Assembly: Gemstone.Timeseries (in Gemstone.Timeseries.dll) Version: 1.0.128 -- Release Build+e2476c52e94864f123f37e60764c948e49eb89eb
C#View SourceRequest Example
public Ticks RealTime { get; }

Property Value

Ticks

Remarks

Because the measurements being received by remote devices are often measured relative to GPS time, these timestamps are typically more accurate than the local clock. As a result, we can use the latest received timestamp as the best local time measurement we have (ignoring transmission delays); but, even these times can be incorrect so we still have to apply reasonability checks to these times. To do this, we use the local system time and the LeadTime value to validate the latest measured timestamp. If the newest received measurement timestamp gets too old or creeps too far into the future (both validated + and - against defined lead time property value), we will fall back on local system time. Note that this creates a dependency on a fairly accurate local clock - the smaller the lead time deviation tolerance, the better the needed local clock accuracy. For example, a lead time deviation tolerance of a few seconds might only require keeping the local clock synchronized to an NTP time source; but, a sub-second tolerance would require that the local clock be very close to GPS time.

See Also