code: func (p *Pool) removeStaleSelf() error {
  	t := newTransaction()
  	t.purgeStalePool(p.id)
  	if err := t.exec(); err != nil {
  		return err
  	}
  	return nil
  }
docs: // removeStaleSelf will check if the current machine recently failed hard
  // (e.g. due to power failuer) by checking if p.id is in the set of active
  // pools. If p.id is still "active" according to the database, it means
  // there was a hard failure, and so removeStaleSelf then re-queues the
  // stale jobs. removeStaleSelf should only be run when the Pool is started.