code: func (m *Manager) Stop() {
  	m.mtxScrape.Lock()
  	defer m.mtxScrape.Unlock()
  
  	for _, sp := range m.scrapePools {
  		sp.stop()
  	}
  	close(m.graceShut)
  }
docs: // Stop cancels all running scrape pools and blocks until all have exited.