//! Daemon liveness tracking.
//!
//! Records the wall-clock second of the last activity so `/health` and the
//! watchdog can tell how stale the daemon is, and so `/metrics` can report the
//! age at scrape time. The `/metrics` renderer computes the age from this and
//! the scrape time; nothing exposes the raw timestamp as a metric.
use ;
use Timestamp;
static LAST_ACTIVITY: AtomicI64 = new;
/// Record that the daemon did something just now.
/// The unix second of the last recorded activity (`0` before the first).