Reported by RV-Predict (a dynamic race detector) when running the test suite: Data race on field org.apache.catalina.connector.OutputBuffer.suspended: {{{ Concurrent read in thread T115 (locks held: {}) ----> at org.apache.catalina.connector.OutputBuffer.isSuspended(OutputBuffer.java:200) at org.apache.catalina.connector.Response.isSuspended(Response.java:400) at org.apache.catalina.connector.Response.isAppCommitted(Response.java:341) at org.apache.catalina.connector.ResponseFacade.isCommitted(ResponseFacade.java:345) at org.apache.catalina.connector.ResponseFacade.setHeader(ResponseFacade.java:542) at org.apache.catalina.core.TestAsyncContextImpl$Bug50753Servlet$1.run(TestAsyncContextImpl.java:1153) at org.apache.catalina.core.AsyncContextImpl$RunnableWrapper.run(AsyncContextImpl.java:562) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) T115 is created by T114 at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:1010) Concurrent write in thread T114 (locks held: {Monitor@4c031101}) ----> at org.apache.catalina.connector.OutputBuffer.setSuspended(OutputBuffer.java:210) at org.apache.catalina.connector.Response.setSuspended(Response.java:392) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:167) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:277) - locked Monitor@4c031101 at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:259) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) T114 is created by T112 at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:1010) }}}
One more report: Data race on field org.apache.catalina.connector.OutputBuffer.suspended: {{{ Concurrent write in thread T38 (locks held: {Monitor@c32a9c3}) ----> at org.apache.catalina.connector.OutputBuffer.setSuspended(OutputBuffer.java:210) at org.apache.catalina.connector.Response.setSuspended(Response.java:392) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:167) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:277) - locked Monitor@c32a9c3 at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:259) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) T38 is created by T36 at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:1010) Concurrent read in thread T39 (locks held: {}) ----> at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:402) at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:97) at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:90) at org.apache.catalina.connector.TestCoyoteAdapter$AsyncServlet$1.run(TestCoyoteAdapter.java:387) T39 is created by T38 at org.apache.catalina.connector.TestCoyoteAdapter$AsyncServlet.doGet(TestCoyoteAdapter.java:409) }}}
Another race on OutputBuffer.closed: Data race on field org.apache.catalina.connector.OutputBuffer.closed: {{{ Concurrent write in thread T21 (locks held: {}) ----> at org.apache.catalina.connector.OutputBuffer.close(OutputBuffer.java:297) at org.apache.catalina.connector.Response.finishResponse(Response.java:453) at org.apache.catalina.connector.CometEventImpl.close(CometEventImpl.java:96) at org.apache.catalina.comet.TestCometProcessor$AsyncCometCloseThread.run(TestCometProcessor.java:665) T21 is created by T20 at org.apache.catalina.comet.TestCometProcessor$AsyncCometCloseValve.invoke(TestCometProcessor.java:648) Concurrent read in thread T20 (locks held: {Monitor@78eabf38}) ----> at org.apache.catalina.connector.OutputBuffer.isClosed(OutputBuffer.java:220) at org.apache.catalina.connector.Response.isClosed(Response.java:408) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673) at org.apache.tomcat.util.net.Nio2Endpoint$SocketProcessor.doRun(Nio2Endpoint.java:1074) at org.apache.tomcat.util.net.Nio2Endpoint$SocketProcessor.run(Nio2Endpoint.java:1033) - locked Monitor@78eabf38 at org.apache.tomcat.util.net.Nio2Endpoint$SocketProcessor.run(Nio2Endpoint.java:1032) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) T20 is created by T19 at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:1010) }}}
Fixed in trunk and 8.0.x for 8.0.27 onwards.