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Are there any tuning parameters to speed up my application which stalls when sending messages to a JMS queue

I'm trying to execute an application under (reasonable) load. What is happening under load is that when trying to place a message onto a queue, the application stalls for about 4 seconds before completing the send. The strange part is that immediately after doing this, the next message takes a matter of milliseconds to place onto the queue. The message is in fact the same message - so the message size isn't a factor.
The application is using Spring Boot 2.1.6, Apache Qpid 0.43.0 as the JMS/AMQP provider.
The message bus being used is Azure ServiceBus, but I have observed the same behaviour using Artemis.
On the Apache Qpid JmsConnectionFactory, I've tried fiddling with the properties "forceSyncSend".
I've tried using the Spring Boot CachingConnectionFactory to cache message producers only. I have increased the default cache size from 1 to 20 without any success.
I've looked at the JmsTemplate parameters but can't find any parameters in regard to message producers (plenty with listeners but that's another story).
The code doing the sending is quite simple:
private void sendToQueue(Object message, String queueName) {
jmsTemplate.convertAndSend(queueName, message, (Message jmsMessage) -> {
jmsMessage.setStringProperty(OBJECT_TYPE_PARAMETER, message.getClass().getSimpleName());
return jmsMessage;
});
Is there anything obvious to try? Are there any tuning parameters to stop this stalling happening?
The load on the system is not trivial, but it is not excessive (it needs to go a lot higher than where it is at the moment!)
Any ideas?

RabbitMQ Java API queuePurge() method called on Qpid returns PurgeOK response with zero message count

I am integration testing a component that uses RabbitMQ client (amqp-client version 5.7.0) with an embedded Apache Qpid server object.
When calling the Channel.queuePurge() method, the queue is purged. I can verify that with the getMessageCount() method. But the queuePurge() method returns a PurgeOk object, which always has 0 message count. The documentation says the PurgeOK returns the message count that was purged.
//The queue has 1 message.
int f = getMessageCount();
//verify message count
assertEquals(f, 1);
//purge
com.rabbitmq.client.AMQP.Queue.PurgeOk purgeOK= channel.queuePurge(queueName);
//the next test fails.
//Shouldn't the purgeOK have count 1, to denote that one message was purged?
assertEquals(purgeOK.getMessageCount(), 1);
This happens only when testing with embedded Qpid server. The same test case with an actual running instance of Rabbit MQ is giving the expected.
Is this a known issue? Is there a better way to unit test the purge feature?

It wasn't a known issue, I have raised an issue for this defect in Qpid Broker-J. Thank you for your help in discovering this.

Slow message consumption using AmazonSQSClient

So, i used concurrency in spring jms 50-100, allowing max connections upto 200. Everything is working as expected but if i try to retrieve 100k messages from queue, i mean there are 100k messages on my sqs and i reading them through the spring jms normal approach.
#JmsListener
Public void process (String message) {
count++;
Println (count);
//code
}
I am seeing all the logs in my console but after around 17k it starts throwing exceptions
Something like : aws sdk exception : port already in use.
Why do i see this exception and how do. I get rid of it?
I tried looking on the internet for it. Couldn't find anything.
My setting :
Concurrency 50-100
Set messages per task :50
Client acknowledged
timestamp=10:27:57.183, level=WARN , logger=c.a.s.j.SQSMessageConsumerPrefetch, message={ConsumerPrefetchThread-30} Encountered exception during receive in ConsumerPrefetch thread,
javax.jms.JMSException: AmazonClientException: receiveMessage.
at com.amazon.sqs.javamessaging.AmazonSQSMessagingClientWrapper.handleException(AmazonSQSMessagingClientWrapper.java:422)
at com.amazon.sqs.javamessaging.AmazonSQSMessagingClientWrapper.receiveMessage(AmazonSQSMessagingClientWrapper.java:339)
at com.amazon.sqs.javamessaging.SQSMessageConsumerPrefetch.getMessages(SQSMessageConsumerPrefetch.java:248)
at com.amazon.sqs.javamessaging.SQSMessageConsumerPrefetch.run(SQSMessageConsumerPrefetch.java:207)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: com.amazonaws.SdkClientException: Unable to execute HTTP request: Address already in use: connect
Update : i looked for the problem and it seems that new sockets are being created until every sockets gets exhausted.
My spring jms version would be 4.3.10
To replicate this problem just do the above configuration with the max connection as 200 and currency set to 50-100 and push some 40k messages to the sqs queue.. One can use https://github.com/adamw/elasticmq this as a local stack server which replicates Amazon sqs.. After being done till here. Comment jms listener and use soap ui load testing and call the send message to fire many messages. Just because you commented #jmslistener annotation, it won't consume messages from queue. Once you see that you have sent 40k messages, stop. Uncomment #jmslistener and restart the server.
Update :
DefaultJmsListenerContainerFactory factory =
new DefaultJmsListenerContainerFactory();
factory.setConnectionFactory(connectionFactory);
factory.setDestinationResolver(new DynamicDestinationResolver());
factory.setErrorHandler(Throwable::printStackTrace);
factory.setConcurrency("50-100");
factory.setSessionAcknowledgeMode(Session.CLIENT_ACKNOWLEDGE);
return factory;
Update :
SQSConnectionFactory connectionFactory = new SQSConnectionFactory( new ProviderConfiguration(), amazonSQSclient);
Update :
Client configuration details :
Protocol : HTTP
Max connections : 200
Update :
I used cache connection factory class and it seems. I read on stack overflow and in their official documentation to not use cache connection factory class and default jms listener container factory.
https://stackoverflow.com/a/21989895/5871514
It's gives the same error that i got before though.
update
My goal is to get a 500 tps, i.e i should be able to consume that much.. So i tried this method and it seems I can reach 100-200, but not more than that.. Plus this thing is a blocker at high concurrency .. If you use it.. If you have some better solution to achieve it.. I am all ears.
**updated **
I am using amazonsqsclient

Starvation on the Consumer
One possible optimization that JMS clients tend to implement, is a message consumption buffer or "prefetch". This buffer is sometimes tunable via the number of messages or by a buffer size in bytes.
The intention is to prevent the consumer from going to the server every single time it receives a messages, rather than pulling multiple messages in a batch.
In an environment where you have many "fast consumers" (which is the opinionated view these libraries may take), this prefetch is set to a somewhat high default in order to minimize these round trips.
However, in an environment with slow message consumers, this prefetch can be a problem. The slow consumer is holding up messaging consumption for those prefetched messages from the faster consumer. In a highly concurrent environment, this can cause starvation quickly.
That being the case the SQSConnectionFactory has a property for this:
SQSConnectionFactory sqsConnectionFactory = new SQSConnectionFactory( new ProviderConfiguration(), amazonSQSclient);
sqsConnectionFactory.setNumberOfMessagesToPrefetch(0);
Starvation on the Producer (i.e. via JmsTemplate)
It's very common for these JMS implementations to expect be interfaced to the broker via some intermediary. These intermediaries actually cache and reuse connections or use a pooling mechanism to reuse them. In the Java EE world, this is usually taken care of a JCA adapter or other method on a Java EE server.
Because of the way Spring JMS works, it expects an intermediary delegate for the ConnectionFactory to exist to do this caching/pooling. Otherwise, when Spring JMS wants to connect to the broker, it will attempt to open a new connection and session (!) every time you want to do something with the broker.
To solve this, Spring provides a few options. The simplest being the CachingConnectionFactory, which caches a single Connection, and allows many Sessions to be opened on that Connection. A simple way to add this to your #Configuration above would be something like:
#Bean
public ConnectionFactory connectionFactory(AmazonSQSClient amazonSQSclient) {
SQSConnectionFactory sqsConnectionFactory = new SQSConnectionFactory(new ProviderConfiguration(), amazonSQSclient);
// Doing the following is key!
CachingConnectionFactory connectionfactory = new CachingConnectionFactory();
connectionfactory.setTargetConnectionFactory(sqsConnectionFactory);
// Set the #connectionfactory properties to your liking here...
return connectionFactory;
}
If you want something more fancy as a JMS pooling solution (which will pool Connections and MessageProducers for you in addition to multiple Sessions), you can use the reasonably new PooledJMS project's JmsPoolConnectionFactory, or the like, from their library.

javax.websocket - timeout for delivering message

I'm using javax.websocket API in my app. I send messages from server to client like this:
Future<Void> messageFuture = session.getAsyncRemote().sendText(message);
messageFutures.add(messageFuture); // List<Future<Void>> messageFutures
I use async API because I really care about performance and cannot make server wait until each message is delivered, because server does smth like this:
for (i = 1..N) {
result = doStuff()
sendMessage(result)
}
So it is impossible to wait for message delivery each iteration.
After I send all the messages I need to wait for all the Future's to be finished (all messages are delivered). And to be safe I need to use some timeout like "if server sends message to client and client doesn't confirm receipt in 30 seconds then consider websocket connection broken" - as far as I understand it should be possible to do with websockets since they work over TCP.
There is a method session.setMaxIdleTimeout(long):
Set the non-zero number of milliseconds before this session will be
closed by the container if it is inactive, ie no messages are either
sent or received. A value that is 0 or negative indicates the session
will never timeout due to inactivity.
but I really not sure if it is what I want (is it?). So how can I set a timeout like I described using javax.websocket API?

The idle timeout could cover your case, but it is not designed to. The idle timeout applies more to the case where a client makes a connection, but is using it only infrequently.
The more precise feature for checking a timeout when sending is setAsyncSendTimeout.
Using both of these allows you to configure for the case where a client may leave a connection idle for minutes at a time, but the server expects relatively quick messages acknowledgements.
In my experience with Spring, the timeout implementation provided by Spring is not actually configurable. See How do you quickly close a nonresponsive websocket in Java Spring Tomcat? I am not sure whether this is applicable to your websocket implementation.

How to set the timeout for a MQTT client?

I'm using the IA92 Java implementation for MQTT, which allows me to connect to a MQTT broker. In order to establish the connection, I'm doing something like this:
// Create connection spec
String mqttConnSpec = "tcp://the_server#the_port";
// Create the client and connect
mqttClient = MqttClient.createMqttClient(mqttConnSpec, null);
mqttClient.connect("the_id", true, 666);
The problem is that sometimes the server takes too much time to send a response, and it throws a timeout exception:
org.apache.harmony.luni.platform.OSNetworkSystem.connectStreamWithTimeoutSocket(OSNetworkSystem.java:130)
at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:246)
at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:533)
at java.net.Socket.connect(Socket.java:1055)
at com.ibm.mqtt.j2se.MqttJava14NetSocket.<init>((null):-1)
at com.ibm.mqtt.j2se.MqttJavaNetSocket.setConnection((null):-1)
at com.ibm.mqtt.Mqtt.tcpipConnect((null):-1)
at com.ibm.mqtt.MqttBaseClient.doConnect((null):-1)
at com.ibm.mqtt.MqttBaseClient.connect((null):-1)
at com.ibm.mqtt.MqttClient.connect((null):-1)
at com.ibm.mqtt.MqttClient.connect((null):-1)
What I need to do is setting a timeout manually, instead of letting the mqtt client decide that. The documentation says: There are also methods for setting attributes of the MQ Telemetry Transport connection, such as timeouts and retries.
But, honestly, I haven't found anything about it. I have taken a look at the whole javadoc reference and there's no evidence of timeout configuration. I can't see the source code since it's not open source.
So how can I set the timeout for the Mqtt connection?

If you have confusion you can go to MqttConnectionOptions for detail.
String userName="Ohelig";
String password="Pojke";
MqttClient client = new MqttClient("tcp://192.168.1.4:1883","Sending");
MqttConnectOptions authen = new MqttConnectOptions();
authen.setUserName(userName);
authen.setPassword(password.toCharArray());
authen.setKeepAliveInterval(30);
authen.setConnectionTimeout(300);
client.connect(authen);

I don't know anything about ia92, but I'd imagine that the 666 in the connect() call is what you're trying to set the timeout to?
The timeout the documentation is referring to is probably the keepalive timeout. This is the maximum number of seconds (chosen by the client) that can elapse without communication between the server and client. I think this is what you're most interested in.
Retries on the other hand are most likely to refer to the retrying of messages that seem to have gone astray when sending messages with QoS>0. This will be something handled by the client library code though, rather than the broker. This is something that comes into play only after you've connected though, so I very much doubt it's your problem.
To be sure that the keepalive timeout is being set correctly, I'd try pointing your client at a modified mosquitto broker. You can modify mqtt3_handle_connect() in src/read_handle_server.c to print out the keepalive value when you connect. This will ensure it's doing what you think, but won't help with the actual problem I'm afraid!

What broker do you use? Really Small Message Broker V1.1 Alpha, Mosquitto, the broker that comes with IBM WebSphere? You need to set this timeout value in your server configuration. Because the system works that way. You set a keep alive value in your broker and send a ping from the client before that interval expires, in order not for the broker to close the client-server connection, and the process restarts. Actually, even if that interval expires, server will still not close the connection until the 'grace period' ends. See http://public.dhe.ibm.com/software/dw/webservices/ws-mqtt/mqtt-v3r1.html#connect