[Question] Performances issue

[Gsantomaggio]

Hi,
Sorry for using the issue, but the discussion is not enabled.

Env

• RabbitMQ 4.1.0-beta.4
• Mac M1
• Single Quorum queue
• Single TCP connection
• Single Session
• Single Sender

Scope

Performance testing

Code

Given the following code:

for i := 0; i < 500_000; i++ {
... 
r, err := sender.SendWithReceipt(ctx, amqp.NewMessage(make([]byte, 10)), nil)
if err != nil {
	// deal with error
}
 state, err := r.Wait(ctx)
if err != nil {
		// deal with error
}
...
}

The rate is ~3.700 messages per second.

I tried a different approach, with:

type CallbackConfirmation func(message *amqp.Message, state DeliveryState, err error)

func (m *Publisher) PublishAsyncConfirmation(ctx context.Context, message *amqp.Message, callback CallbackConfirmation) error {

sendReceipt, err := m.sender.SendWithReceipt(ctx, message, nil)
	if err != nil {
		return nil
	}
	if atomic.AddInt32(&m.pending, 1) == int32(m.maxInFlight) {
		m.condition.L.Lock()
		m.condition.Wait()
		m.condition.L.Unlock()
	}
	go func(sr amqp.SendReceipt) {
		state, err := sr.Wait(ctx)
		atomic.AddInt32(&m.pending, -1)
		m.condition.Signal()
		callback(message, state, err)
	}(sendReceipt)
	return nil
}

The send and confirmation "async" rate is ~ 35.747 messages per second, which is ~10 times faster.

Questions:

• Is my second approach safe? I am looking inside the code, and it should be secure. I just wanted to ask for more confirmation.
• Any advice about sending performance?

Thank you