Kubernetes 中常用代码解读

Rate Limit Queue

func (r *ItemExponentialFailureRateLimiter) When(item interface{}) time.Duration {
    r.failuresLock.Lock()
    defer r.failuresLock.Unlock()

    exp := r.failures[item]
    r.failures[item] = r.failures[item] + 1

    // The backoff is capped such that ‘calculated’ value never overflows.
    backoff := float64(r.baseDelay.Nanoseconds()) * math.Pow(2, float64(exp))
    if backoff > math.MaxInt64 {
        return r.maxDelay
    }

    calculated := time.Duration(backoff)
    if calculated > r.maxDelay {
        return r.maxDelay
    }
    return calculated
}