When the next alarm should fire.
+1 ms while the chain has work (a fresh invocation is a fresh CPU budget, which lets a chain of 10 ms units do what no single invocation could); otherwise the idle interval.
Optional
When the next alarm should fire.
+1 ms while the chain has work (a fresh invocation is a fresh CPU budget, which lets a chain of 10 ms units do what no single invocation could); otherwise the idle interval.