grafana/k6 · error

the iteration rate must be more than 0

Error message

the iteration rate must be more than 0

What it means

ConstantArrivalRateConfig.Validate rejected a rate <= 0 (e.g. rate: 0 or negative). Rate is set but must be a positive number of iterations per timeUnit; a zero rate would mean a test that never starts any iterations.

Source

Thrown at lib/executor/constant_arrival_rate.go:96

	var arrRatePerSec float64
	if maxVUs != 0 { // TODO: do something better?
		ratio := big.NewRat(maxVUs, carc.MaxVUs.Int64)
		arrRate := big.NewRat(carc.Rate.Int64, int64(timeUnit))
		arrRate.Mul(arrRate, ratio)
		arrRatePerSec, _ = getArrivalRatePerSec(arrRate).Float64()
	}

	return fmt.Sprintf("%.2f iterations/s for %s%s", arrRatePerSec, carc.Duration.Duration,
		carc.getBaseInfo(maxVUsRange))
}

// Validate makes sure all options are configured and valid
func (carc *ConstantArrivalRateConfig) Validate() []error {
	errors := carc.BaseConfig.Validate()
	if !carc.Rate.Valid {
		errors = append(errors, fmt.Errorf("the iteration rate isn't specified"))
	} else if carc.Rate.Int64 <= 0 {
		errors = append(errors, fmt.Errorf("the iteration rate must be more than 0"))
	}

	if carc.TimeUnit.TimeDuration() <= 0 {
		errors = append(errors, fmt.Errorf("the timeUnit must be more than 0"))
	}

	if !carc.Duration.Valid {
		errors = append(errors, fmt.Errorf("the duration is unspecified"))
	} else if carc.Duration.TimeDuration() < minDuration {
		errors = append(errors, fmt.Errorf(
			"the duration must be at least %s, but is %s", minDuration, carc.Duration,
		))
	}

	if !carc.PreAllocatedVUs.Valid {
		errors = append(errors, fmt.Errorf("the number of preAllocatedVUs isn't specified"))
	} else if carc.PreAllocatedVUs.Int64 < 0 {
		errors = append(errors, fmt.Errorf("the number of preAllocatedVUs can't be negative"))

View on GitHub (pinned to 01ffac6f24)

Solutions

1. Set rate to a positive integer such as rate: 200
2. Combine it with a suitable timeUnit, e.g. rate: 600, timeUnit: '1m' for 10 it/s

When it happens

Trigger: Thrown at lib/executor/constant_arrival_rate.go:96 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of grafana/k6@01ffac6f24 (2026-08-18). Data as JSON: /api/errors/af6f478319e4d5f7. Report an issue: GitHub.