Network connection leak in asynchronous servlet ----------------------------------------------- Key: WFLY-4413 URL: https://issues.jboss.org/browse/WFLY-4413 Project: WildFly Issue Type: Bug Components: Web (Undertow) Affects Versions: 8.1.0.Final, 8.2.0.Final Environment: Linux Reporter: jeremy_lv lv Assignee: Stuart Douglas Priority: Blocker Labels: undertow {panel:title=Phenomenon|borderStyle=dashed|borderColor=#ccc|titleBGColor=#F7D6C1|bgColor=#FFFFCE} When the connection is suddenly terminated during the period we access the asynchronous servlet application, the connection will be leaked. However, the connection won't be leak when we access the synchronous servlet application. {panel} *Some of the stacktrace are as follows:* {panel:title=Stacktrace|borderStyle=dashed|borderColor=#ccc|titleBGColor=#F7D6C1|bgColor=#FFFFCE} 14:34:23,751 ERROR [io.undertow.request] (default task-22) Blocking request fail at io.undertow.servlet.spec.HttpServletResponseImpl.responseDone(HttpSer at io.undertow.servlet.spec.AsyncContextImpl$3.run(AsyncContextImpl.java at io.undertow.servlet.spec.AsyncContextImpl$6.run(AsyncContextImpl.java at io.undertow.servlet.spec.AsyncContextImpl$TaskDispatchRunnable.run(As at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor. at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor at java.lang.Thread.run(Thread.java:724) [rt.jar:1.7.0_25] Caused by: java.io.IOException: Connection reset by peer at sun.nio.ch.FileDispatcherImpl.write0(Native Method) [rt.jar:1.7.0_25] at sun.nio.ch.SocketDispatcher.write(SocketDispatcher.java:47) [rt.jar:1 at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:94) [rt.jar:1.7.0 at sun.nio.ch.IOUtil.write(IOUtil.java:51) [rt.jar:1.7.0_25] at sun.nio.ch.SocketChannelImpl.write(SocketChannelImpl.java:466) [rt.ja at org.xnio.nio.NioSocketConduit.write(NioSocketConduit.java:150) at io.undertow.server.protocol.http.HttpResponseConduit.processWrite(Htt at io.undertow.server.protocol.http.HttpResponseConduit.flush(HttpRespon at io.undertow.conduits.AbstractFixedLengthStreamSinkConduit.flush(Abstr at org.xnio.conduits.ConduitStreamSinkChannel.flush(ConduitStreamSinkCha at io.undertow.channels.DetachableStreamSinkChannel.flush(DetachableStre at org.xnio.channels.Channels.flushBlocking(Channels.java:63) at io.undertow.servlet.spec.ServletOutputStreamImpl.close(ServletOutputS at io.undertow.servlet.spec.HttpServletResponseImpl.closeStreamAndWriter at io.undertow.servlet.spec.HttpServletResponseImpl.responseDone(HttpSer ... 6 more {panel} *Here's the test war code you can used to reproduce this phenomenon:* {code:title=AsyncDemoServlet.java|borderStyle=solid} import java.io.IOException; import javax.servlet.AsyncContext; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @WebServlet(urlPatterns="/asyncDemoServlet",asyncSupported=true) public class AsyncDemoServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); //Execute the business logic in sub-thread. AsyncContext ctx = request.startAsync(); new Thread(new Executor(ctx)).start(); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } public class Executor implements Runnable { private AsyncContext ctx = null; public Executor(AsyncContext ctx){ this.ctx = ctx; } public void run(){ try { ctx.getResponse().getOutputStream().write("aaa".getBytes()); //wait for 5 seconds to simulate the business logic. Thread.sleep(5000); ctx.getResponse().getOutputStream().flush(); ctx.complete(); } catch (Exception e) { e.printStackTrace(); } } } } {code}