Can't run TinyKV with TinySQL

[Moonm3n]

In the default configuration, SchedulerHeartbeatTickInterval is less than RaftBaseTickInterval.

func NewDefaultConfig() *Config {
	return &Config{
		SchedulerAddr:            "127.0.0.1:2379",
		StoreAddr:                "127.0.0.1:20160",
		LogLevel:                 getLogLevel(),
		Raft:                     true,
		// RaftBaseTickInterval is one seconde.
		RaftBaseTickInterval:     1 * time.Second,
		RaftHeartbeatTicks:       2,
		RaftElectionTimeoutTicks: 10,
		RaftLogGCTickInterval:    10 * time.Second,
		RaftLogGcCountLimit:                 128000,
		SplitRegionCheckTickInterval:        10 * time.Second,
		// SchedulerHeartbeatTickInterval is one hundred milliseconds.
		SchedulerHeartbeatTickInterval:      100 * time.Millisecond,
		SchedulerStoreHeartbeatTickInterval: 10 * time.Second,
		RegionMaxSize:                       144 * MB,
		RegionSplitSize:                     96 * MB,
		DBPath:                              "/tmp/badger",
	}
}

So Raft leader will never send heartbeat to the scheduler, the scheduler will never get the region information too.

TinySQL gets the following error:

[FATAL] [session.go:864] ["check bootstrapped failed"] [error="[tikv:9001]PD server timeout"]

[Connor1996]

why if it's less than raft base tick interval, raft leader never send heartbeat to the scheduler

[Moonm3n]

The use of "never" isn't quite accurate. To be precise, leaders will never send RegionHeartbeat by tick.

The interval of PeerTickSchedulerHeartbeat is equal to SchedulerHeartbeatTickInterval divided by RaftBaseTickInterval.

t.schedules[int(PeerTickSchedulerHeartbeat)].interval = int64(cfg.SchedulerHeartbeatTickInterval / baseInterval)

The result of it is 0, so PeerTickSchedulerHeartbeat will not be scheduled.

func (t *ticker) schedule(tp PeerTick) {
	sched := &t.schedules[int(tp)]
	if sched.interval <= 0 {
		sched.runAt = -1
		return
	}
	sched.runAt = t.tick + sched.interval
}

Leaders will never send RegionHeartbeat by tick.

func (d *peerMsgHandler) onTick() {
	if d.stopped {
		return
	}
	d.ticker.tickClock()
	if d.ticker.isOnTick(PeerTickRaft) {
		d.onRaftBaseTick()
	}
	if d.ticker.isOnTick(PeerTickRaftLogGC) {
		d.onRaftGCLogTick()
	}
	if d.ticker.isOnTick(PeerTickSchedulerHeartbeat) { // always false
		d.onSchedulerHeartbeatTick()
	}
	if d.ticker.isOnTick(PeerTickSplitRegionCheck) {
		d.onSplitRegionCheckTick()
	}
	d.ctx.tickDriverSender <- d.regionId
}

func (d *peerMsgHandler) onSchedulerHeartbeatTick() {
	d.ticker.schedule(PeerTickSchedulerHeartbeat)

	if !d.IsLeader() {
		return
	}
	d.HeartbeatScheduler(d.ctx.schedulerTaskSender)
}