Method OnAskforLearn

src/algorithm/learner.cpp:262–310

}

void Learner :: OnAskforLearn(const PaxosMsg & oPaxosMsg)
{
    BP->GetLearnerBP()->OnAskforLearn();
    
    PLGHead("START Msg.InstanceID %lu Now.InstanceID %lu Msg.from_nodeid %lu MinChosenInstanceID %lu", 
            oPaxosMsg.instanceid(), GetInstanceID(), oPaxosMsg.nodeid(),
            m_poCheckpointMgr->GetMinChosenInstanceID());
    
    SetSeenInstanceID(oPaxosMsg.instanceid(), oPaxosMsg.nodeid());

    if (oPaxosMsg.proposalnodeid() == m_poConfig->GetMyNodeID())
    {
        //Found a node follow me.
        PLImp("Found a node %lu follow me.", oPaxosMsg.nodeid());
        m_poConfig->AddFollowerNode(oPaxosMsg.nodeid());
    }
    
    if (oPaxosMsg.instanceid() >= GetInstanceID())
    {
        return;
    }

    if (oPaxosMsg.instanceid() >= m_poCheckpointMgr->GetMinChosenInstanceID())
    {
        if (!m_oLearnerSender.Prepare(oPaxosMsg.instanceid(), oPaxosMsg.nodeid()))
        {
            BP->GetLearnerBP()->OnAskforLearnGetLockFail();

            PLGErr("LearnerSender working for others.");

            if (oPaxosMsg.instanceid() == (GetInstanceID() - 1))
            {
                PLGImp("InstanceID only difference one, just send this value to other.");
                //send one value
                AcceptorStateData oState;
                int ret = m_oPaxosLog.ReadState(m_poConfig->GetMyGroupIdx(), oPaxosMsg.instanceid(), oState);
                if (ret == 0)
                {
                    BallotNumber oBallot(oState.acceptedid(), oState.acceptednodeid());
                    SendLearnValue(oPaxosMsg.nodeid(), oPaxosMsg.instanceid(), oBallot, oState.acceptedvalue(), 0, false);
                }
            }
            
            return;
        }
    }
    
    SendNowInstanceID(oPaxosMsg.instanceid(), oPaxosMsg.nodeid());
}

void Learner :: SendNowInstanceID(const uint64_t llInstanceID, const nodeid_t iSendNodeID)
{