Spring Boot WebSocket无CONNECTED帧及inboundChannel堆积咨询

故障表现 #

• 生产环境Spring Boot服务端WebSocket Broker收到客户端发送的CONNECT帧后，未返回对应的CONNECTED帧
• 故障初期为偶发，后续逐步恶化，最终浏览器侧发起的所有CONNECT请求均无法收到响应
• 浏览器控制台日志：
  
• 服务端控制台日志：
  

初步排查结论 #

故障发生时inboundChannel队列存在大量任务积压，是CONNECT帧无响应的直接原因。故障时刻采集的WebSocketMessageBrokerStats日志如下：

2022-06-01 18:22:59,943 INFO  Thread-id-74- springframework.web.socket.config.WebSocketMessageBrokerStats: WebSocketSession[130 current WS(129)-HttpStream(1)-HttpPoll(0), 225 total, 0 closed abnormally (0 connect failure, 0 send limit, 2 transport error)], stompSubProtocol[processed CONNECT(220)-CONNECTED(132)-DISCONNECT(0)], stompBrokerRelay[null], inboundChannel[pool size = 2, active threads = 2, queued tasks = 10774, completed tasks = 31806], outboundChannel[pool size = 2, active threads = 0, queued tasks = 0, completed tasks = 570895], sockJsScheduler[pool size = 1, active threads = 1, queued tasks = 134, completed tasks = 1985]

从日志可观测到核心异常：inboundChannel线程池核心线程数仅为2，且2个线程全部处于活跃执行状态，队列中排队等待执行的任务数高达10774，处理能力完全跟不上任务提交速度。

核心疑问 #

哪些业务场景或配置问题会引发inboundChannel队列出现任务排队堆积？

客户端现有STOMP配置（Angular） #

const config: StompJS.StompConfig = {
      brokerURL: this.serverUrl,
      connectHeaders: {
        ccid: this.cookieService.get('ccid'),
        username: `${this.globalContext.get('me')['username']}`,
      },
      debug: (str) => {
        this.loggerService.log(this.sessionId, ' | ', str);
      },
      webSocketFactory: () => {
        return new SockJS(this.serverUrl);
      },
      logRawCommunication: true,
      reconnectDelay: 3000,
      heartbeatIncoming: 100,
      heartbeatOutgoing: 100,
      discardWebsocketOnCommFailure: true,
      connectionTimeout: 4000
    };

内容的提问来源于stack exchange，提问作者Dave Ranjan