Struct BackoffPolicy 

pub struct BackoffPolicy {
    pub first: Duration,
    pub max: Duration,
    pub factor: f64,
    pub jitter: JitterPolicy,
}

Retry backoff policy.

Encapsulates parameters that determine how retry delays grow:

• BackoffPolicy::factor — multiplicative growth factor;
• BackoffPolicy::first — the initial delay;
• BackoffPolicy::max — the maximum delay cap.

Fields

first: Duration

Initial delay before the first retry.

max: Duration

Maximum delay cap for retries.

factor: f64

Multiplicative growth factor (>= 1.0 recommended).

jitter: JitterPolicy

Jitter policy to prevent thundering herd.

Implementations

impl BackoffPolicy

pub fn next(&self, attempt: u32) -> Duration

Computes the delay for the given attempt number (0-indexed).

The base delay is first × factor^attempt, clamped to BackoffPolicy::max. Jitter is applied to the clamped base, but the result is never fed back into subsequent calculations — each attempt derives its base independently.

Notes

• If factor is less than 1.0, delays decrease with higher attempts (not typical).
• If factor equals 1.0, delay remains constant at first (up to max).
• If factor is greater than 1.0, delays grow exponentially up to max.

Trait Implementations

impl Clone for BackoffPolicy

fn clone(&self) -> BackoffPolicy

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BackoffPolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for BackoffPolicy

fn default() -> Self

Returns a strategy with:

• factor = 1.0 (constant delay);
• first = 100ms;
• max = 30s.

impl Copy for BackoffPolicy