Websocket 块在客户端插入 pull/power 丢失时没有超时

Question

我的 Tomcat + Spring websocket 应用程序有一个奇怪的问题。当用户在没有发送"closing"信号的情况下断开连接时，由于掉电或插头拔出，线程将在大约10秒后阻塞.

此函数上的线程阻塞：

org.springframework.web.socket.WebSocketSession.sendMessage(WebSocketMessage<?> wsm) throws IOException;

我尝试在我的 AppConfig 中添加一行以尝试设置 3 秒的超时，但它似乎无法正常工作，因为 块似乎继续向上抛出异常前 15 分钟.

@Bean(name="servletServerContainerFactoryBean")
public int maxSessionIdleTimeout() {
  return 3000;
}

这是事件 SocketTimeoutException

之后的堆栈跟踪

Step: 2304
SendB -> test isOpen -> sendMes -> Done -> Finished Send.
SendB -> test2 isOpen -> sendMes -> User closed connection during packet sending: s01
Propogating exception up!
java.io.IOException: java.net.SocketTimeoutException
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:315)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:250)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendPartialString(WsRemoteEndpointImplBase.java:223)
    at org.apache.tomcat.websocket.WsRemoteEndpointBasic.sendText(WsRemoteEndpointBasic.java:49)
    at org.springframework.web.socket.adapter.standard.StandardWebSocketSession.sendTextMessage(StandardWebSocketSession.java:197)
    at org.springframework.web.socket.adapter.AbstractWebSocketSession.sendMessage(AbstractWebSocketSession.java:102)
    at org.infpls.noxio.game.module.game.session.NoxioSession.sendPacket(NoxioSession.java:40)
    at org.infpls.noxio.game.module.game.dao.lobby.GameLobby.step(GameLobby.java:117)
    at org.infpls.noxio.game.module.game.dao.lobby.GameLobby$GameLoop.run(GameLobby.java:274)
Caused by: java.net.SocketTimeoutException
    at org.apache.tomcat.websocket.server.WsRemoteEndpointImplServer.doWrite(WsRemoteEndpointImplServer.java:81)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.writeMessagePart(WsRemoteEndpointImplBase.java:494)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:309)
    ... 8 more
## CRITICAL ## Ejecting player: test2 :: Exception thrown on packet send...
java.io.IOException: java.net.SocketTimeoutException
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:315)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:250)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendPartialString(WsRemoteEndpointImplBase.java:223)
    at org.apache.tomcat.websocket.WsRemoteEndpointBasic.sendText(WsRemoteEndpointBasic.java:49)
    at org.springframework.web.socket.adapter.standard.StandardWebSocketSession.sendTextMessage(StandardWebSocketSession.java:197)
    at org.springframework.web.socket.adapter.AbstractWebSocketSession.sendMessage(AbstractWebSocketSession.java:102)
    at org.infpls.noxio.game.module.game.session.NoxioSession.sendPacket(NoxioSession.java:40)
    at org.infpls.noxio.game.module.game.dao.lobby.GameLobby.step(GameLobby.java:117)
    at org.infpls.noxio.game.module.game.dao.lobby.GameLobby$GameLoop.run(GameLobby.java:274)
Caused by: java.net.SocketTimeoutException
    at org.apache.tomcat.websocket.server.WsRemoteEndpointImplServer.doWrite(WsRemoteEndpointImplServer.java:81)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.writeMessagePart(WsRemoteEndpointImplBase.java:494)
    at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:309)
    ... 8 more
Finished Send. Step Finished.

一次阻塞线程 15 分钟是一个主要问题。任何关于为什么会发生这种情况以及如何解决它的信息将不胜感激。谢谢！

Answer 1

终于找到答案了。其实是系统设置。

Source

How many times to retry before deciding that something is wrong and
it is necessary to report this suspicion to network layer. Minimal RFC
value is 3, it is default, which corresponds to  3sec-8min depending on
RTO.
/proc/sys/net/ipv4/tcp_retries2

Websocket 块在客户端插入 pull/power 丢失时没有超时

Websocket blocks without timing out on client plug pull/power loss

java

sockets

websocket

spring-websocket