code: func (pm *ProtocolManager) BroadcastTxs(txs types.Transactions) {
  	var txset = make(map[*peer]types.Transactions)
  
  	// Broadcast transactions to a batch of peers not knowing about it
  	for _, tx := range txs {
  		peers := pm.peers.PeersWithoutTx(tx.Hash())
  		for _, peer := range peers {
  			txset[peer] = append(txset[peer], tx)
  		}
  		log.Trace("Broadcast transaction", "hash", tx.Hash(), "recipients", len(peers))
  	}
  	// FIXME include this again: peers = peers[:int(math.Sqrt(float64(len(peers))))]
  	for peer, txs := range txset {
  		peer.AsyncSendTransactions(txs)
  	}
  }
docs: // BroadcastTxs will propagate a batch of transactions to all peers which are not known to
  // already have the given transaction.