Function spawn_timed 

pub fn spawn_timed<F>(
    future: F,
    counter: Option<Counter>,
) -> JoinHandle<F::Output> 
where
    F: Future + Send + 'static,
    F::Output: Send + 'static,

Spawns future on the current tokio runtime, attaching CPU-time accounting when counter is Some. When None, the future is spawned as-is with no per-poll overhead.

Equivalent to:

// Some(counter):
crate::spawn_in_current_span(future.cpu_timed(counter))
// None:
crate::spawn_in_current_span(future)

Use this when spawning background tasks (e.g. a transform’s housekeeping loop) whose CPU usage should be attributed back to a component. Wrap the future with [tracing::Instrument] (or similar adapters) before passing it in if you want those adapters’ per-poll work included in the CPU-time measurement.

The current tracing span is attached to the spawned task.