[Tarantool-patches] [PATCH v2 09/11] raft: introduce state machine
Serge Petrenko
sergepetrenko at tarantool.org
Mon Sep 21 11:20:52 MSK 2020
19.09.2020 18:50, Vladislav Shpilevoy пишет:
> And my new changes on top of it, in a separate commit.
>
> ====================
>
> diff --git a/src/box/applier.cc b/src/box/applier.cc
> index c352faf5e..10186ab91 100644
> --- a/src/box/applier.cc
> +++ b/src/box/applier.cc
> @@ -885,6 +885,11 @@ static int
> applier_handle_raft(struct applier *applier, struct xrow_header *row)
> {
> assert(iproto_type_is_raft_request(row->type));
> + if (applier->instance_id == 0) {
> + diag_set(ClientError, ER_PROTOCOL, "Can't apply a Raft request "
> + "from an instance without an ID");
> + return -1;
> + }
>
> struct raft_request req;
> struct vclock candidate_clock;
> diff --git a/src/box/raft.c b/src/box/raft.c
> index 07a49351f..b3ab94bd7 100644
> --- a/src/box/raft.c
> +++ b/src/box/raft.c
> @@ -347,6 +347,7 @@ raft_process_msg(const struct raft_request *req, uint32_t source)
> if (req->vote != 0) {
> switch (raft.state) {
> case RAFT_STATE_FOLLOWER:
> + case RAFT_STATE_LEADER:
> /*
> * Can't respond on vote requests when Raft is disabled.
> */
> @@ -386,6 +387,12 @@ raft_process_msg(const struct raft_request *req, uint32_t source)
> "indirect votes are not allowed");
> break;
> }
> + if (raft.leader != 0) {
> + say_info("RAFT: vote request is skipped - the "
> + "leader is already known - %u",
> + raft.leader);
> + break;
> + }
> /*
> * Either the term is new, or didn't vote in the current
> * term yet. Anyway can vote now.
> @@ -415,16 +422,6 @@ raft_process_msg(const struct raft_request *req, uint32_t source)
> }
> raft_sm_become_leader();
> break;
> - case RAFT_STATE_LEADER:
> - /*
> - * If the node is still a leader, it ignores all votes.
> - * Indeed, if the received vote would be from a new
> - * term, the node would bump its own term and would
> - * enter the follower state by now. If the vote is from
> - * the current term, then the leader can freely ignore
> - * it.
> - */
> - break;
> default:
> unreachable();
> }
> @@ -466,6 +463,12 @@ end:
> void
> raft_process_heartbeat(uint32_t source)
> {
> + /*
> + * Raft handles heartbeats from all instances, including anon instances
> + * which don't participate in Raft.
> + */
> + if (source == 0)
> + return;
> /*
> * When not a candidate - don't wait for anything. Therefore do not care
> * about the leader being dead.
> @@ -746,6 +749,7 @@ raft_sm_schedule_new_vote(uint32_t new_vote)
> {
> say_info("RAFT: vote for %u, follow", new_vote, raft.volatile_term);
> assert(raft.volatile_vote == 0);
> + assert(raft.leader == 0);
> assert(raft.state == RAFT_STATE_FOLLOWER);
> raft.volatile_vote = new_vote;
> raft_sm_pause_and_dump();
> @@ -929,15 +933,8 @@ raft_cfg_election_quorum(void)
> return;
> if (raft.vote_count < raft_election_quorum())
> return;
> - /*
> - * The node is a candidate. It means its state if fully synced with
> - * disk. Otherwise it would be a follower.
> - */
> - assert(!raft.is_write_in_progress);
> - raft.state = RAFT_STATE_LEADER;
> - raft.leader = instance_id;
> + raft_sm_become_leader();
> raft_broadcast_new_state();
> - box_update_ro_summary();
> }
>
> void
Hi! Thanks for the fixes!
LGTM.
--
Serge Petrenko
More information about the Tarantool-patches
mailing list