mqtt client gets disconnected frequently when running on multiple threads

问题

I have mosca mqtt broker runnning. I connect to it using paho-mqtt from a python client. I have two threads which I run parallely in my code, one to receive messages and the other to publish.

def SendCommand(rpm,valve_opening):
    control_packet = {
                    ########
                }
    print(control_packet)
    print('sending command')
#    client.publish("cmd",control_packet)

def on_connect(client, userdata, flags, rc):
    if rc==0:
        print("connected OK Returned code=",rc)
        client.subscribe('data/#')
    else:
        print("Bad connection Returned code=",rc)

def on_disconnect(client, userdata, rc):
   print("Client Got Disconnected")
   print("rc value: " + str(rc))

   if rc != 0:
       print('Unexpected MQTT disconnection. Will auto-reconnect')      
   else:
       print('rc value:' + str(rc))                   


def on_publish(client,userdata,message):
    print("published.")



def on_message(client, userdata, message):
    # obs = []   calculate based on message

def Agent():
    action, _states = model.predict(obs)
    SendCommand(fan_rpm,chw_flow)

def Controls():
    schedule.every(30).seconds.do(Agent)
    while True:        
        schedule.run_pending()

def mqttConnection():
    global client
    client = mqtt.Client(client_id='Client_test', clean_session=True) #create new instance
    client.on_connect = on_connect
    client.on_disconnect = on_disconnect
    client.on_message = on_message
    client.on_publish = on_publish
    print("connecting to broker")
    client.connect(broker_address, port=port) #connect to broker
    client.loop_forever() #stop the loop

#########################################################################################
import threading
t1 = threading.Thread(target=Controls)
t1.daemon = False
t1.start()
t2 = threading.Thread(target=mqttConnection)
t2.daemon = False
t2.start()

Every time a publish happens client gets disconnected.

sending command
published
Client Got Disconnected
rc value: 1
Unexpected MQTT disconnection. Will auto-reconnect
connected OK Returned code= 0

I tried commenting the client.publish line, still I then disconnection is happening. So my doubt is this disconnection something to do with multi thread or some problem with broker itself. can anyone help me with this?

来源：https://stackoverflow.com/questions/58705344/mqtt-client-gets-disconnected-frequently-when-running-on-multiple-threads