On Oct 7, 2016, at 1:21 PM, Steven Schlansker <sschlansker(a)opentable.com&gt; wrote: [ apologies for the rampant cross-posting, it looks like I might have been sending this to old mailing lists, and getting lost in the void? ] Hello resteasy-dev, I am trying to use the new JAX-RS 2.0 @Suspended AsyncResponse mechanism to write a service that expects many idling connections (awaiting an event via long-poll), and therefore seems like a good candidate for asynchronous responses, so as not to use a large number of waiting threads. The resource code is very simple: @GET @Produces(MediaType.APPLICATION_JSON) public void watchForChanges( @Suspended AsyncResponse asyncResponse, @QueryParam("since") long since) { controller.watchForChanges(since, asyncResponse::resume); } The intent is that watchForChanges places the (inferred) Consumer<ResponseObject> on a queue, and returns immediately. Later on a background thread comes by and completes the request. However, when testing with say 20 clients, it sure looks like the end result is still a thread per request model: "qtp1718322084-43" - Thread t@43 java.lang.Thread.State: WAITING at sun.misc.Unsafe.park(Native Method) - parking to wait for <3537ebd5> (a java.util.concurrent.CountDownLatch$Sync) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997) at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304) at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:231) at org.jboss.resteasy.core.SynchronousExecutionContext$SynchronousAsynchronousResponse.initialRequestThreadFinished(SynchronousExecutionContext.java:127) at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:411) at org.jboss.resteasy.core.SynchronousDispatcher.invokePropagateNotFound(SynchronousDispatcher.java:247) at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:225) at org.jboss.resteasy.plugins.server.servlet.FilterDispatcher.doFilter(FilterDispatcher.java:62) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1676) <snip Jetty handler / filter chain> at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:319) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:253) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671) at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589) at java.lang.Thread.run(Thread.java:745) The concept of a "SynchronousAsynchronousResponse" and implementation of in particular SynchronousDispatcher#invoke seem to be totally not what I want: /** * Callback by the initial calling thread. This callback will probably do nothing in an asynchronous environment * but will be used to simulate AsynchronousResponse in vanilla Servlet containers that do not support * asychronous HTTP. * */ request.getAsyncContext().getAsyncResponse().initialRequestThreadFinished(); What am I doing wrong? How do I get truly asynchronous processing? This is with RESTEasy 3.0.18 running on Jetty 9.3.11 Thanks for any advice, Steven

From: "Steven Schlansker" <sschlansker(a)opentable.com&gt; To: resteasy-dev(a)lists.jboss.org Sent: Tuesday, October 11, 2016 7:16:29 PM Subject: Re: [resteasy-dev] RESTEasy asynchronous processing with @Suspended -- actually synchronous? Hi again, I was somewhat disappointed to not get an answer here, but I did a fair amount more digging, and managed to find Filter30Dispatcher (which just moved recently for upcoming 3.1.0) Unfortunately then I found that the documentation does not mention this class at all, but at least it exists! (at least not on http://docs.jboss.org/resteasy/docs/3.0.19.Final/userguide/html_single/in... ) So far it seems to work well. Better than FilterDispatcher, at least :) Let me know if there's any gotchas or other bits that I've missed. Best, Steven > On Oct 7, 2016, at 1:21 PM, Steven Schlansker <sschlansker(a)opentable.com&gt; > wrote: > > [ apologies for the rampant cross-posting, it looks like I might have been > sending this to old mailing lists, and getting lost in the void? ] > > Hello resteasy-dev, > > I am trying to use the new JAX-RS 2.0 @Suspended AsyncResponse mechanism to > write > a service that expects many idling connections (awaiting an event via > long-poll), > and therefore seems like a good candidate for asynchronous responses, so as > not > to use a large number of waiting threads. > > The resource code is very simple: > > @GET > @Produces(MediaType.APPLICATION_JSON) > public void watchForChanges( > @Suspended AsyncResponse asyncResponse, > @QueryParam("since") long since) > { > controller.watchForChanges(since, asyncResponse::resume); > } > > The intent is that watchForChanges places the (inferred) > Consumer<ResponseObject> on a queue, > and returns immediately. Later on a background thread comes by and > completes the request. > > However, when testing with say 20 clients, it sure looks like the end > result is still a > thread per request model: > > > "qtp1718322084-43" - Thread t@43 > java.lang.Thread.State: WAITING > at sun.misc.Unsafe.park(Native Method) > - parking to wait for <3537ebd5> (a > java.util.concurrent.CountDownLatch$Sync) > at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304) > at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:231) > at > org.jboss.resteasy.core.SynchronousExecutionContext$SynchronousAsynchronousResponse.initialRequestThreadFinished(SynchronousExecutionContext.java:127) > at > org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:411) > at > org.jboss.resteasy.core.SynchronousDispatcher.invokePropagateNotFound(SynchronousDispatcher.java:247) > at > org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:225) > at > org.jboss.resteasy.plugins.server.servlet.FilterDispatcher.doFilter(FilterDispatcher.java:62) > at > org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1676) > <snip Jetty handler / filter chain> > at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:319) > at > org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:253) > at > org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) > at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) > at > org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) > at > org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303) > at > org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148) > at > org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136) > at > org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671) > at > org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589) > at java.lang.Thread.run(Thread.java:745) > > > > The concept of a "SynchronousAsynchronousResponse" and implementation of in > particular SynchronousDispatcher#invoke seem to be totally not what I > want: > /** > * Callback by the initial calling thread. This callback will > probably do nothing in an asynchronous environment > * but will be used to simulate AsynchronousResponse in vanilla > Servlet containers that do not support > * asychronous HTTP. > * > */ > request.getAsyncContext().getAsyncResponse().initialRequestThreadFinished(); > > > What am I doing wrong? How do I get truly asynchronous processing? > > This is with RESTEasy 3.0.18 running on Jetty 9.3.11 > > Thanks for any advice, > Steven _______________________________________________ resteasy-dev mailing list resteasy-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/resteasy-dev

Resteasy is using org.jboss.resteasy.plugins.server.servlet.HttpServlet30Dispatcher in processing @Suspended. We use it in test cases here, ./testsuite/integration-tests/src/test/resources/org/jboss/resteasy/test/asynch ----- Original Message ----- > From: "Steven Schlansker" <sschlansker(a)opentable.com&gt; > To: resteasy-dev(a)lists.jboss.org > Sent: Tuesday, October 11, 2016 7:16:29 PM > Subject: Re: [resteasy-dev] RESTEasy asynchronous processing with @Suspended -- actually synchronous? > > Hi again, > > I was somewhat disappointed to not get an answer here, but I did a fair > amount more digging, > and managed to find Filter30Dispatcher (which just moved recently for > upcoming 3.1.0) > > Unfortunately then I found that the documentation does not mention this > class at all, but at least it exists! > (at least not on > http://docs.jboss.org/resteasy/docs/3.0.19.Final/userguide/html_single/in... > ) > > So far it seems to work well. Better than FilterDispatcher, at least :) > Let me know if there's any gotchas or other bits that I've missed. > > Best, > Steven > >> On Oct 7, 2016, at 1:21 PM, Steven Schlansker <sschlansker(a)opentable.com&gt; >> wrote: >> >> [ apologies for the rampant cross-posting, it looks like I might have been >> sending this to old mailing lists, and getting lost in the void? ] >> >> Hello resteasy-dev, >> >> I am trying to use the new JAX-RS 2.0 @Suspended AsyncResponse mechanism to >> write >> a service that expects many idling connections (awaiting an event via >> long-poll), >> and therefore seems like a good candidate for asynchronous responses, so as >> not >> to use a large number of waiting threads. >> >> The resource code is very simple: >> >> @GET >> @Produces(MediaType.APPLICATION_JSON) >> public void watchForChanges( >> @Suspended AsyncResponse asyncResponse, >> @QueryParam("since") long since) >> { >> controller.watchForChanges(since, asyncResponse::resume); >> } >> >> The intent is that watchForChanges places the (inferred) >> Consumer<ResponseObject> on a queue, >> and returns immediately. Later on a background thread comes by and >> completes the request. >> >> However, when testing with say 20 clients, it sure looks like the end >> result is still a >> thread per request model: >> >> >> "qtp1718322084-43" - Thread t@43 >> java.lang.Thread.State: WAITING >> at sun.misc.Unsafe.park(Native Method) >> - parking to wait for <3537ebd5> (a >> java.util.concurrent.CountDownLatch$Sync) >> at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) >> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) >> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997) >> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304) >> at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:231) >> at >> org.jboss.resteasy.core.SynchronousExecutionContext$SynchronousAsynchronousResponse.initialRequestThreadFinished(SynchronousExecutionContext.java:127) >> at >> org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:411) >> at >> org.jboss.resteasy.core.SynchronousDispatcher.invokePropagateNotFound(SynchronousDispatcher.java:247) >> at >> org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:225) >> at >> org.jboss.resteasy.plugins.server.servlet.FilterDispatcher.doFilter(FilterDispatcher.java:62) >> at >> org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1676) >> <snip Jetty handler / filter chain> >> at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:319) >> at >> org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:253) >> at >> org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) >> at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) >> at >> org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) >> at >> org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303) >> at >> org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148) >> at >> org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136) >> at >> org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671) >> at >> org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589) >> at java.lang.Thread.run(Thread.java:745) >> >> >> >> The concept of a "SynchronousAsynchronousResponse" and implementation of in >> particular SynchronousDispatcher#invoke seem to be totally not what I >> want: >> /** >> * Callback by the initial calling thread. This callback will >> probably do nothing in an asynchronous environment >> * but will be used to simulate AsynchronousResponse in vanilla >> Servlet containers that do not support >> * asychronous HTTP. >> * >> */ >> request.getAsyncContext().getAsyncResponse().initialRequestThreadFinished(); >> >> >> What am I doing wrong? How do I get truly asynchronous processing? >> >> This is with RESTEasy 3.0.18 running on Jetty 9.3.11 >> >> Thanks for any advice, >> Steven > > _______________________________________________ > resteasy-dev mailing list > resteasy-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/resteasy-dev > _______________________________________________ resteasy-dev mailing list resteasy-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/resteasy-dev