There are not any hard-coded limits inside RabbitMQ broker. The broker will utilize all available resources (unless you set limits on some of them, they are called watermarks in RabbitMQ terminology). There are some limitations put by Erlang itself, like maximum number of concurrent processes, but if you theoretically can reach them on single node … Read more
I assume your system looks like the following. You have a REST service, which receives requests from the client. It converts the requests into commands which the business logic can understand. You put these commands into a queue. You have a single or multiple workers which can process and remove these commands from the queue … Read more
Personally I am quite fond of message queues and think they are arguably the most under-utilized IPC in the unix world. They are fast and easy to use. A couple of thoughts: Some of this is just fashion. Old things become new again. Add a shiny do-dad on message queues and they may be next … Read more
Years ago, I asked myself the same question. I was looking at NServiceBus to work with a different message queue, but the question was the same. I decided not to use NServiceBus. 6 Month later, I realized I had re-built half of what NServiceBus did… only much more poorly. The equivalent question of why would … Read more
RabbitMQ is probably doing persistence on those messages. I think you need to set the message priority or another option in messages to not do persistence. Performance will improve 10x then. You should expect at least 100K messages/second through an AMQP broker. In OpenAMQ we got performance up to 300K messages/second. AMQP was designed for … Read more
Well, let’s take a closer look at the scenario you are describing above. I think it’s important to paste the documentation immediately prior to the snippet in your question to provide context: Section 4.7 of the AMQP 0-9-1 core specification explains the conditions under which ordering is guaranteed: messages published in one channel, passing through … Read more
Remember that while JavaScript is single-threaded, all of node’s I/O and calls to native APIs are either asynchronous (using platform-specific mechanisms), or run on a separate thread. (This is all handled through libuv.) So when there’s data available on a socket or a native API function has returned, we need a synchronized way to invoke … Read more
Theoretically anything can be stored/sent as a message. You actually don’t want to store anything on the queues. The system works most efficiently if the queues are empty most of the time. You can send anything you want to the queue with two preconditions: The thing you are sending can be converted to and from … Read more
A Looper is a message handling loop: it reads and processes items from a MessageQueue. The Looper class is usually used in conjunction with a HandlerThread (a subclass of Thread). A Handler is a utility class that facilitates interacting with a Looper—mainly by posting messages and Runnable objects to the thread’s MessageQueue. When a Handler … Read more