etcdserver/api/v2stats/server.go
func (ss *ServerStats) RecvAppendReq(leader string, reqSize int) {
	ss.Lock()
	defer ss.Unlock()

	now := time.Now()

	ss.State = raft.StateFollower
	if leader != ss.LeaderInfo.Name {
		ss.LeaderInfo.Name = leader
		ss.LeaderInfo.StartTime = now
	}

	ss.recvRateQueue.Insert(
		&RequestStats{
			SendingTime: now,
			Size:        reqSize,
		},
	)
	ss.RecvAppendRequestCnt++
}
func (ss *ServerStats) RecvAppendReq(leader string, reqSize int) {
	ss.Lock()
	defer ss.Unlock()

	now := time.Now()

	ss.State = raft.StateFollower
	if leader != ss.LeaderInfo.Name {
		ss.LeaderInfo.Name = leader
		ss.LeaderInfo.StartTime = now
	}

	ss.recvRateQueue.Insert(
		&RequestStats{
			SendingTime: now,
			Size:        reqSize,
		},
	)
	ss.RecvAppendRequestCnt++
}
// RecvAppendReq updates the ServerStats in response to an AppendRequest
// from the given leader being received