Very strange behavior after new a task on echo example

[zxarcg]

I only create a test class, code is as followed, then in EchoServerHandler class , add TestUserThread _thread = new TestUserThread(); then server always can't receive client message。Remove last line , i can receive message。but if i use "System.Threading.Thread thread = new System.Threading.Thread(SendMessage);..", i can receive message. Too strange, please help me.

public class TestUserThread { public TestUserThread() { Task.Factory.StartNew(SendMessage, TaskCreationOptions.LongRunning);

        //System.Threading.Thread thread = new System.Threading.Thread(SendMessage);
        //thread.IsBackground = true;
        //a.Start();
    }
    void SendMessage(){
         while(true){ Thread.Sleep(100);}
     }

}

[nayato]

if you could put it out (let's say in a branch of your fork) I could check it out. It's hard to understand the problem without the context.

[zxarcg]

hi nayato,

please view https://github.com/zxarcg/DotNetty 。

[zxarcg]

hi nayato,

Through debug, i found reason. because in "bool RunAllTasks(PreciseTimeSpan timeout) in SingleThreadEventExecutor.cs" , task.Run() is synchronous, and my task action code is " while(true)..", so next tasks always can't run . so i only exit from task's while clause , EchoServerHandler ChannelRead method can be called.

is it a bug ?

i think maybe it's reason is netty 4.x thread model, all read/write is executed serial by netty nioeventloop, and my business task is wrapped by netty task, and is executed by serial, so my business task impact io read /write.

[nayato]

It certainly isn't DotNetty's bug. You are expected not to block the event loop and that's exactly what you do with while (true). You may still maintain the tight loop semantics if you'd like by scheduling the same method to event loop through IEventExecutor.Execute(..).