tokio::task

Function consume_budget

Source
pub async fn consume_budget()
Available on crate feature rt only.
Expand description

Consumes a unit of budget and returns the execution back to the Tokio runtime if the task’s coop budget was exhausted.

The task will only yield if its entire coop budget has been exhausted. This function can be used in order to insert optional yield points into long computations that do not use Tokio resources like sockets or semaphores, without redundantly yielding to the runtime each time.

§Examples

Make sure that a function which returns a sum of (potentially lots of) iterated values is cooperative.

async fn sum_iterator(input: &mut impl std::iter::Iterator<Item=i64>) -> i64 {
    let mut sum: i64 = 0;
    while let Some(i) = input.next() {
        sum += i;
        tokio::task::consume_budget().await
    }
    sum
}