Solana中的投票流程

Posted 2021-09-04 mutourend

1. 引言

前序博客有：

• Solana代码解析
• Solana中的PoH

2. TPU中收集投票

		let (verified_vote_packets_sender, verified_vote_packets_receiver) = unbounded();
        let cluster_info_vote_listener = ClusterInfoVoteListener::new(
            exit,
            cluster_info.clone(),
            verified_vote_packets_sender,
            poh_recorder,
            vote_tracker,
            bank_forks.clone(),
            subscriptions.clone(),
            verified_vote_sender,
            gossip_verified_vote_hash_sender,
            replay_vote_receiver,
            blockstore.clone(),
            bank_notification_sender,
            cluster_confirmed_slot_sender,
        );

TPU中的监听投票流程与banking_stage是并行进行的。

投票的维度有2种，分别为：

• vote for label packets
• vote for transactions

		let (verified_vote_label_packets_sender, verified_vote_label_packets_receiver) =
            unbounded();
        let (verified_vote_transactions_sender, verified_vote_transactions_receiver) = unbounded();

并行处理的流程有：

• 1）recv_loop()：通过gossip协议收集投票信息 -》 验证投票中的交易和label信息-》分别发送transactions vote和label packets vote

let (labels, votes) = cluster_info.get_votes(&mut cursor);
.....
let (vote_txs, packets) = Self::verify_votes(votes, labels);
 verified_vote_transactions_sender.send(vote_txs)?;
verified_vote_label_packets_sender.send(packets)?;

• 2）bank_send_loop()：
  2.1）借助receive_and_process_vote_packets()，若当前Validator为leader，则将相应的packets插入到VerifiedVotePackets中；若不是leader，则清空VerifiedVotePackets。
  2.2）为leader时，借助get_latest_votes()，过滤VerifiedVotePackets中，version版本大于last_version的packets。
  2.3）将过滤后的packets通过verified_packets_sender发出，并更新bank中记录的最新version。
• 3）process_votes_loop()：
  verify_for_unrooted_optimistic_slots()：Returns any optimistic slots that were not rooted
  log_unrooted_optimistic_slots()：
  progress_leader_schedule_epoch()：Update with any newly calculated epoch state about future epochs
  purge_stale_state()：Purge any outdated slot data
  listen_and_confirm_votes()：
  add_new_optimistic_confirmed_slots()：只对confirmed slots进行处理。

3. TVU在replay stage进行投票