Function tokio::task::consume_budget

pub async fn consume_budget()

Available on tokio_unstable and crate feature rt only.

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.

Note: This is an unstable API. The public API of this type may break in 1.x releases. See the documentation on unstable features for details.

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
}