m.Set(driveWaitingIO, float64(disk.Metrics.TotalWaiting), labels...)

	// Append the api label for the drive API latencies.
	labels = append(labels, "api", "")
	lastIdx := len(labels) - 1
	for apiName, latency := range disk.Metrics.LastMinute {
		labels[lastIdx] = "storage." + apiName
		m.Set(driveAPILatencyMicros, float64(latency.Avg().Microseconds()),
			labels...)
	}
}