1. 程式人生 > >java.net.SocketInputStream.socketRead0 掛起執行緒

java.net.SocketInputStream.socketRead0 掛起執行緒

背景

現在的Java EE 系統通常都依賴於遠端服務,需要通過網路請求獲取遠端服務。不管是使用什麼協議(HTTP,HTTPS,JDBC 等)請求遠端服務,Java VM最終都將委託給Socket去實現。首先會通過connect方法與遠端服務建立連線,連線建立成功後就可以 write/read 與遠端服務實現資料通訊。

Socket.connect()、Socket.write()、Socket.read() 方法呼叫都被稱為阻塞IO呼叫。這些呼叫由於網路延時、伺服器響應緩慢等問題往往會導致執行緒掛起。

請看下面的客戶端和遠端服務通訊過程: 引用

問題

公司推送服務突然出現問題,該服務需要HTTP遠端呼叫第三方的服務提供商。

問題排查

通過檢視日誌發現谷歌的FCM推送了最後一條訊息,並且沒有推送完成。然後 jps -lvm 命令超出推送服務程序號,再用jstack -l pid檢視堆疊資訊。發現有大量的java.net.SocketInputStream.socketRead0 執行緒處於掛起狀態:

"http-nio-10251-exec-1213" #86023 daemon prio=5 os_prio=0 tid=0x00007f838c0f8000 nid=0x1f9 runnable [0x00007f83693bd000]
   java.lang.Thread.State: RUNNABLE
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
	at java.net.SocketInputStream.read(SocketInputStream.java:171)
	at java.net.SocketInputStream.read(SocketInputStream.java:141)
	at sun.security.ssl.InputRecord.readFully(InputRecord.java:465)
	at sun.security.ssl.InputRecord.read(InputRecord.java:503)
	at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:983)
	- locked <0x00000000da936c90> (a java.lang.Object)
	at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:940)
	at sun.security.ssl.AppInputStream.read(AppInputStream.java:105)
	- locked <0x00000000da936ca8> (a sun.security.ssl.AppInputStream)
	at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
	at java.io.BufferedInputStream.read1(BufferedInputStream.java:286)
	at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
	- locked <0x00000000da9372b8> (a java.io.BufferedInputStream)
	at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:735)
	at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:678)
	at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1569)
	- locked <0x00000000da180448> (a sun.net.www.protocol.https.DelegateHttpsURLConnection)
	at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1474)
	- locked <0x00000000da180448> (a sun.net.www.protocol.https.DelegateHttpsURLConnection)
	at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480)
	at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(HttpsURLConnectionImpl.java:338)
	at com.google.api.client.http.javanet.NetHttpResponse.<init>(NetHttpResponse.java:37)
	at com.google.api.client.http.javanet.NetHttpRequest.execute(NetHttpRequest.java:105)
	at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:981)
	at com.google.firebase.messaging.FirebaseMessaging$1.execute(FirebaseMessaging.java:254)
	at com.google.firebase.messaging.FirebaseMessaging$1.execute(FirebaseMessaging.java:240)
	at com.google.firebase.internal.CallableOperation.call(CallableOperation.java:36)
	at com.google.firebase.messaging.FirebaseMessaging.send(FirebaseMessaging.java:157)
	at com.google.firebase.messaging.FirebaseMessaging.send(FirebaseMessaging.java:143)
	at com.manniu.sns.core.service.FCMPush.push(FCMPush.java:105)
	at com.manniu.sns.core.controller.SnsController.push(SnsController.java:99)
	at sun.reflect.GeneratedMethodAccessor74.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	- locked <0x00000000da70ba18> (a org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)

   Locked ownable synchronizers:
	- <0x00000000da813810> (a java.util.concurrent.ThreadPoolExecutor$Worker)

"http-nio-10251-exec-1212" #85644 daemon prio=5 os_prio=0 tid=0x00007f8390473800 nid=0x7d04 runnable [0x00007f83683ac000]
   java.lang.Thread.State: RUNNABLE
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
	at java.net.SocketInputStream.read(SocketInputStream.java:171)
	at java.net.SocketInputStream.read(SocketInputStream.java:141)
	at sun.security.ssl.InputRecord.readFully(InputRecord.java:465)
	at sun.security.ssl.InputRecord.read(InputRecord.java:503)
	at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:983)
	- locked <0x00000000dacf5770> (a java.lang.Object)
	- .....
	- .....

問題的解決

由堆疊資訊可以看出大量的執行緒阻塞到socket讀的地方,推斷可能是由於網路延遲或FCM服務連線後沒有響應造成 java.net.SocketInputStream.socketRead0一直阻塞等待讀取。當客戶端與遠端服務連接出現長時間未連線成功或讀寫出現長時間阻塞時,就應該停止連線或讀寫。HTTP連線時可以設定相關connect超時時間和Read超時時間,因此在FCM相關的客戶端程式碼中設定超時時間。

FirebaseOptions options = new FirebaseOptions.Builder()
                    .setCredentials(GoogleCredentials.fromStream(serviceAccount))
                    .setDatabaseUrl(config.getApiSecret())
                    .setReadTimeout(10000)
                    .setConnectTimeout(10000)
                    .build();

結論

由上面的問題可以得出:當 java.net.SocketInputStream.socketRead0 執行緒一直處於掛起阻塞狀態時,很可能的原因是沒有設定超時時間(timeout)。在請求遠端服務時一定要注意設定timeout。

參考