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发现问题：

309~315行这段代码逻辑存在问题，在当前Push执行未结束时，后续对PushProtocols的调用都会启动一个go routine来延迟调用PushProtocols,而若当前执行仍然未结束，那么就会不停的启动go routine来延迟调用PushProtocols，这有些类似死循环的极端场景。

建议方案： 去掉go routine，直接延迟后递归调用，让后续的PushProtocols调用阻塞等待当前Push执行结束，修改后代码类似如下：

// PushProtocols will send protocols supported by us to the other.
// This method will be invoked when new protocol registering.
func (p *protocolExchanger) PushProtocols(pid peer.ID) error {
	// create a signal chan, for listening PUSH_OK back.
	signalC := make(chan struct{}, 1)
	_, loaded := p.pushSignalMap.LoadOrStore(pid, &signalC)
	if loaded {
		time.Sleep(time.Second)
		err := p.PushProtocols(pid)
		if err != nil {
			p.logger.Warnf("[ProtocolExchanger][PushProtocols] push failed, (remote pid: %s)", pid)
		}
		return nil
	}
	defer p.pushSignalMap.Delete(pid)
	// send PUSH , waiting for PUSH_OK back or timeout
	timer := time.NewTimer(exchangeTimeout)
	err := p.sendSelfProtocols(pid, pb.ProtocolExchangerMsg_PUSH)
	if err != nil {
		return err
	}
	select {
	case <-signalC:
		p.logger.Infof("[ProtocolExchanger][PushProtocols] push success, (remote pid: %s)", pid)
	case <-timer.C:
		return ErrPushProtocolTimeout
	}
	return nil
}