Protected ReadonlyperiodThe poll period — also the unit any per-poll hold/window law counts in.
Whether the poll timer is currently running.
The live subscriber count.
Force-stop polling regardless of subscriber count (server shutdown).
ProtectedonCalled whenever polling stops (including a stop with no timer running). A feed carrying cross-poll memory clears it here, so a fresh subscription never compares against a reading from a previous session.
Poll once now (also driven by the interval). Never overlaps itself: a tick arriving while readTick is still in flight returns immediately.
ProtectedreadOne tick to the sink, carrying the report when a source exists. A thrown read is swallowed and the whole tick skipped — the engine is momentarily busy, and the other gauges wait one period rather than publish beside a report that never came.
ProtectedstartStart the timer if it isn't already running — the activation policy's door.
ProtectedstopStop the timer if it is running, then let the subclass drop its per-run state.
Register a subscriber; starts polling on the first one.
Drop a subscriber; stops polling when the last one leaves.
Ticks while there are subscribers, polling the LatencyReportSource when there is one.