nixfleet_agent/runtime/workers/
advance_ticker.rs

1//! Periodic timer that emits [`super::super::ReducerInput::AgentAdvanceTick`]
2//! at a fixed interval. Mirror of the CP runtime's `PlanTick`.
3//!
4//! Cadence: 5s, intentionally tighter than CP's 15s `PLAN_TICK_INTERVAL`
5//! because sustained-failure detection on the agent is more time-
6//! critical than channel-edges checks on the CP. A late tick means
7//! Soaking → Failed transitions lag by ≤5s; that's acceptable per
8//! RFC-0005 §6's threshold semantics.
9
10use std::time::Duration;
11
12use nixfleet_proto::clock::ClockHandle;
13use tokio::sync::mpsc;
14use tokio::task::JoinHandle;
15
16use super::super::{ReducerInput, ShutdownToken};
17
18const TICK_INTERVAL: Duration = Duration::from_secs(5);
19
20pub fn spawn(
21    _clock: ClockHandle,
22    input_tx: mpsc::Sender<ReducerInput>,
23    shutdown: ShutdownToken,
24) -> JoinHandle<()> {
25    tokio::spawn(async move {
26        let mut shutdown_rx = shutdown.into_inner();
27        let mut ticker =
28            tokio::time::interval_at(tokio::time::Instant::now() + TICK_INTERVAL, TICK_INTERVAL);
29        ticker.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);
30
31        loop {
32            tokio::select! {
33                biased;
34                _ = &mut shutdown_rx => {
35                    tracing::info!(
36                        target: "shutdown",
37                        task = "agent_advance_ticker",
38                        "task shut down",
39                    );
40                    return;
41                }
42                _ = ticker.tick() => {
43                    if let Err(err) = input_tx.send(ReducerInput::AgentAdvanceTick).await {
44                        tracing::warn!(
45                            target: "agent_advance_ticker",
46                            error = %err,
47                            "reducer input channel closed",
48                        );
49                        return;
50                    }
51                }
52            }
53        }
54    })
55}
nixfleet_agent/runtime/workers/advance_ticker.rs

nixfleet_agent/runtime/workers/
advance_ticker.rs
