NetMQ.NetMQException: Exception of type 'NetMQ.NetMQException' was thrown at NetMQ.Core.Ctx.CreateSocket(ZmqSocketType type)

[jatinrdave]

Environment

NetMQ Version:    4.0.1.8
Operating System: Windows 10
.NET Version:     4.8.1

Expected behaviour

Actual behaviour

Throwing error: "NetMQ.NetMQException: Exception of type 'NetMQ.NetMQException' was thrown.\r\n at NetMQ.Core.Ctx.CreateSocket(ZmqSocketType type)\r\n at NetMQ.NetMQSocket..ctor(ZmqSocketType socketType, String connectionString, DefaultAction defaultAction)\r\n at NetMQ.Sockets.PairSocket.CreateSocketPair(PairSocket& socket1, PairSocket& socket2)\r\n at NetMQ.Core.Utils.StopSignaler..ctor()\r\n at NetMQ.NetMQPoller..ctor()\r\n at NetMQ.NetMQRuntime..ctor()\r\n at WMService.API.Services.Services.WMDispatcherService.<>c__DisplayClass4_0.<InvokeWindowmakerService>b__0()\r\n at System.Threading.Tasks.Task.InnerInvoke()\r\n at System.Threading.Tasks.Task.Execute()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at WMService.API.Services.Services.WMDispatcherService.<InvokeWindowmakerService>d__4.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()\r\n at WMService.API.Services.Services.WindowmakerInterfaceService.<InvokeCalculate>d__5.MoveNext()"

Steps to reproduce the behaviour

• SendReceiveMessage always called when new API request comes.
• Error occurs after much successful responses.

public async Task SendReceiveMessage(string messageString) { ResponseMessage responseMessage = new ResponseMessage() { message = string.Empty };

        //await Task.Delay(1);
        await Task.Factory.StartNew(() => {
            var netMQRuntime = new NetMQRuntime();
            netMQRuntime.Run(RunClient(messageString, responseMessage)); netMQRuntime.Dispose();
        });
        return responseMessage.message;

    }
    async Task RunClient(string messageString, ResponseMessage responseMessage)
    {

        using (var client = new DealerSocket())
        {

            bool more = false;
            try
            {
                string address = "tcp://127.0.0.1";
                string bindingAddress = $"{address}:{tcpPort}";
                client.Connect(bindingAddress);
                client.SendFrame(messageString);
                (responseMessage.message, more) = await client.ReceiveFrameStringAsync();
            }
            catch (Exception ex)
            {
                responseMessage.message = ex.ToString();
            }
            finally
            {
            }
        }
    }

[mlbishop]

Can you print the number of iterations to calculate the number of sockets created? Furthermore, can you print the NetMQException ErrorCode?

I have witnessed the same behavior, in which Dispose does not seem to correctly finish cleaning up the socket. After some time, I reach the socket creation limit and get this exception:

Exception occurred: Exception of type 'NetMQ.NetMQException' was thrown. with error code: TooManyOpenSockets
Stack trace:    at NetMQ.Core.Ctx.CreateSocket(ZmqSocketType type)

Related: https://github.com/zeromq/netmq/issues/1040