code: func (p *roundRobinResourcePool) NumActive() int32 {
  	total := int32(0)
  
  	p.rwMutex.RLock()
  	defer p.rwMutex.RUnlock()
  
  	for _, locPool := range p.pools {
  		total += locPool.Pool.NumActive()
  	}
  	return total
  }
docs: // See ResourcePool for documentation.