Multiple consumers on a queue rabbitmq. Multiple consumers on one RabbitMQ queue.

Multiple consumers on a queue rabbitmq So when I start my app I see only one consumer (and one connection for it) in the rabbit management UI, but to scale up the consuming and increase app productivity I want to increase the number of consumers and connections (one per consumer) for the queue. All message queues that I know of only provide ordering guarantees within the queue itself (Kafka provides ordering guarantee not at queue level but within the partitions within queues). The metric is computed as a fraction of the time that the queue is able to immediately deliver messages to consumers. I want each of my consumers to read messages from queue number 1, 2 and 3. (For every message, different consumer groups should consume it together, but just one consumer in every consumer group can consume this message) See rabbitmq getstarted, you can combine Topics mode & Work queues mode to realize this feature. Fortunately, the producer/consumer problem you described is common and Microsoft has a general-purpose tool for this: the BlockingCollection. Based on the camel apache rabbitmq documentation, this means that a random name is generated for the queue. 2 Load balancing rabbitmqctl list_consumers -p [vhost] Which will list consumers, i. Excuse me I'm a little confused. On the client side (Java) I have multiple consumers which are all listening to their queue like so: QUEUE_1 -> DataConsumer1; QUEUE_2 -> DataConsumer2 They are There is no formula that would produce fair queuing for every type of workload; How much, how uniform and how long does it take to process tasks is important. channel. RabbitMQ / AMQP: multiple queues, single consumer. The operation commands on the same channel is serialized even though they are called in multiple thread ; So. You see, I created a queue and binded it once with . Actually i have a single consumer geting messages from three queues. (one exchange, bound to one queue, direct mode) Publisher produces messages (1,2,3 I have one . – Is there is a way by which we can restrict RabbitMQ Queue to dispatch only a fixed number of messages from the Queue to the consumers? I have 2 Queues Q1 and Q2 and 10 consumers. If you want multiple consumers to the same message, do the following procedure. The consumer has lot of messages waiting for some user to be available. This is good for fast procesing, but not so good for message ordering. I would like to send two types of messages on just one queue. I'm using RabbitMQ to manage multiple servers executing long lasting tasks. If you have more than one service bus instance receiving from the same queue, you need to ensure that the consumers registered on that service bus instance are the same. 1. Not only consumer priority and single active consumer are more obvious choices for most cases, I personally find any design that depends on priority of consumers on a single queue to be very questionable. g. Setting Up RabbitMQ for Parallel Processing. Every consumer can process the messages from Q1 and Q2. A queue could be shared by many consumers but then each consumer would get its share of messages in a round-robin fashion (useful for Those two consumers (consumer-1 and consumer-2) are running in the same application; I found that only one message from a specific queue will be processed at a time. 2 Multiple consumers on one RabbitMQ queue. What is good with AMQP one of your consumer is so fast that can consume all the waiting messages on the queue while the others are waiting. Service instances will use the same queue name as all the RabbitMQ management UI as well as monitoring data endpoints such as that for Prometheus scraping display a metric called consumer capacity (previously consumer utilisation) for individual queues. direct exchange. One more question: is that because queue (rabbitmq in this case) pushing message to consumer? So if consumer doesn't know how to handle this message type he moves it to Each queue will get its own binding to the typed message exchange and get its own copy. Hot Network Questions Boy who can see EM waves but loses the ability because of a thunderstorm I want to process messages in the next way: Consumer 1 - receives messages about employees 1,3,5; Consumer 2 - receives messages about employees 2,4,5. However, here you are asking to serialize multiple queues. How scalable this will be depends on how long it takes to process each message compared to the incoming rate, queue durability, prefetch and how many competing consumers you have on the queue. I come from JS/Node background where event pub/sub pattern works like this: when many consumers subscribe to the same topic with pub/sub pattern, all of them should get the same Is there is a way by which we can restrict RabbitMQ Queue to dispatch only a fixed number of messages from the Queue to the consumers? I have 2 Queues Q1 and Q2 and 10 consumers. consume also has the benefit of allowing Multiple consumer in rabbitmq for multiple queue. RabbitMQ consumers are not adding up. Service instances will use the same queue name as all the other instances, so only one instance will get a message. By having all of your queues go to the same consumer, your code will have to check the type of message to figure out what to do with it. 2 exceptions: fanout queue, where routing key doesn't get used and default "direct" queue where routing key is the name of the destination Consumer thread pool - a pool of threads that consume messages off the RabbitMQ server queues; Queue - a structure that holds messages in FIFO order; It is also possible to attach the same Consumer to multiple First of all, I know there is already an answer to a similar question here, but I am still not sure this is because of RabbitMQ's impossibility or because I haven't researched enough. Changing RabbitMQ Consumer Weights. See tutorials 3 and 4 and please post your questions to rabbitmq-users in the future. Consumer prefetch is an extension to the channel prefetch mechanism. This will send every message to every queue that is bound to the exchange, completely ignoring the routing key. I might not be able to combine these and put all messages into a single rabbitmq level priority RabbitMQ can do this. RabbitMQ publish and consume same queue in simultaneously. 3k 28 Queues What is a Queue? A queue in RabbitMQ is an ordered collection of messages. Want to know the behavior of rabbitmq multiple publisher and consumer. Fanout exchanges replicate the message so multiple queues and consumers will result in multiple writes of the same data to the DB. 3. getChannel(). - there is no way to guarantee a priori that messages are answered in order with multiple consumers. You can then have mulitiple threads running in parallel to manage multiple queues. It's ready-to-use, out of the box. In my application I have a system which publishes messages to multiple queues. 4 How to utilize prefetch count for consumer with . 2 Load balancing I have a RabbitMQ message queue and I want to publish multiple messages to the queue from a web service call ServiceA. However, the consumer is still consuming the messages from the queue. By this setting every consumer can get one message You need a /queue in your scenario; To make last one work in desired way, consumers send AMQ-specific argument when subscribing to the queue: activemq. I want one consumer to get messages from every queues. rabbitmq multiple consumers on a queue- only one get the It doesn't matter if you have multiple queues, multiple exclusive consumers, different brokers, etc. It is not a good idea to use many queues in RabbitMQ. Each queue should only have one consumer. Currently I have 3 consumers for these 3 queues. 5. RabbitMQ publish and consume same queue in I'm using Spring Boot + RabbitMQ server and for one of my Queues I want my multiple consumers to consume the messages serially i. I checked rabbit's page, i seen my queue had 4000 message no send to client. 1 In RabbitMQ, how to handle the conflict between prefetch and 'redelivered' 2 RabbitMq single Consumer with multiple queue. I want to have multiple consumers for the same queue. @oleg-andreyev That stackoverflow answer is not related to my question - it is about single queue with multiple consumers. How can I program to utilize all core where I can process multiple message concurrently. Modified 2 years, 4 months ago. The problem is that i need to get a multiple messages from each of them, but my consumer gets only one per queue and ends getting. e. NET 4. For exemple the message 1 contains more data to be saved compared to mesage 2 for the same product. In short, when the applications start, they each start to listen to the same queue, and I don't understand how they all can expect to receive the same message. consume also has the benefit of allowing You need to use different endpoint names (queues) for each of the services. Springboot RabbitMQ with concurrent consumers. Remember, a QOS value of “5” means that the We're seeing an issue where consumers of our message queues are picking up messages from queues at the top of the alphabetical range. Each exchange will be a default (no type, or a direct exchange with all messages using the same routing key) exchange. BasicConsume() multiple times Multiple Consumer RabbitMQ on one Queue - Java. Service instances will use the same queue name as all the I'd like to have a one consumer that would consume messages from multiple queues. One queue, multiple consumers, with none of them sharing anything. When multiple consumers access a queue, the load-balancing among them takes into account each consumer's capacity and message processing rate. 1 Service Consuming those messages. receive. Share RabbitMQ channel between multiple python processes. Multiple consumers on one RabbitMQ queue. This means all consumers will consume from the same queue. RabbitMQ competing consumers processing 1 message at a time sequentially. 2 Service Publishing messages to RabbitMq via MassTransit. We have two applications: a producer, and a subscriber. This is done by registering a consumer (subscription) on a queue. The preferred method to retrieve multiple messages is to use basic. As an example I have 3 RabbitMQ queues and messages get published to those 3 queues. pika, rabbitmq - get all messages from the queue without consuming them. To listen to multiple queues using the consumer tag, you can use the consumer_tag This happens because RabbitMQ just dispatches a message when the message enters the queue. AMQP 0-9-1 (Advanced Message Queuing Protocol) is a messaging protocol that enables conforming client applications to communicate with conforming messaging middleware brokers. RabbitMQ: How multiple consumers can receive messages Multiple consumer in rabbitmq for multiple queue. I'm not sure what you want an ack for? Are you can have multiple consumers in the same instance/process. Implementation: use RabbitMQ's exchanges and map tasks to the available Is it possible to make multiple consumers to share one single queue in RabbitMQ? I am currently using this php library to work with RabbitMQ, from what I observe, although I have 2 identical instances of a consumer script running, but only one would respond to A single message can be only be delivered to one consumer at a time. If I only register it to listen to 1 queue, it works fine. RabbitMQ multiple consumer subscribe same queue and get same message. The initialization in Sender create connection with rabbitmq; declare the Exchange A; The initialization in Receiver It's about how many messages that one consumer can get from rabbit and cache them on itself to process them. only one consumer receives messages from the queue on RabbitMQ. Consumer capacity will be 0% for queues that have no consumers. Every consumer use 10 seconds in order to handle my process. The way you would like it won't be a queue then. My question is about multiple queues with single consumer which is completely different. consumers are, by default, configured limitless to handle messages. the RabbitMQ bindings between the exchange and queue, using a routing key (if applicable) determine which queue the message is sent to. py I've multiple consumers which are polling on the same queue, and checking the queue every X seconds, basically after X seconds it could be that at least two consumers can launch basic. Queues in RabbitMQ to store messages and feed them to consumers on that queue. RabbitMq single Consumer with multiple queue. Now, I would like to declare one queue "command" where ALL the workers process messages sent to that queue. You need to use 'Work Queues'. when 2 consumer applications are started one after the other, all the preexisting messages are being processed by the first consumer and not being distributed among the two consumers that are up and waiting for messages. I've been reading the RabbitMQ The Data is of such nature what the "Competing Consumer" is not a problem as the messages can get processed in any order and independent. – I've been building a webapp which uses RabbitMQ for jobs. 5. Hot Network Questions How Consumer gets a bunch of messages from the queue; Consumer starts processing a message; Consumer commits the message to mongodb; either due to rabbitmq channel/connection issue, or other type of issue consumer side, the consumer never acknowledges the message; the message as it hasn't been acknowledged is requeued at the Yes it should be ok to run your workers multiple times as that would run multiple instances of your worker listening to your queue to achieve what you want. Let's say I have 2 consumers and 3 queues. When I publish 10000 messages to the queue and the consumer is not started, via rabbitmqctl list_queues I am able to see that test_queue has 10000 messages. 49. Does rabbitmq server gives one message to any one of the consumer at a time and other consumers are ideal at that time? OR. A message is published to "Common Exchange" from which there are bindings to user specific exchanges (e. Improve this answer. Only when the consumer has finished processing one message, only then the consumer should pick up the another message. Why do I have two consumer in the single channel when I only run one consumer. Scaling slightly long running Consumer work - RabbitMQ. How is it decided which of them get it? Is To listen to multiple queues using the basic consumer, you can use the queue_names parameter. Once available, the consumer performs an operation, and when the operation is finished, the messages is acked. I add my code in my question. Rabbit MQ Queues. Create multiple queues, one for each app that is to receive the message, in each queue properties, "bind" a routing tag with the amq. To have each consumer receive the same message, you need to create a queue for each consumer and deliver the same message to each queue. I want to guarantee processing order so, how to avoid the second task to be performed before the first? My solution: make tasks sticky (tasks about A are always sent to the same consumer). They will never receive the same message. Have only 1 consumer instance at all times, or a main consumer and several stand-by consumers. For the sake of simplicity, let’s say we have queue Q RabbitMQ's basic. I need a reference please to a multiple routing keys binded queue. prefetchSize: 1 This setting guarantees that consumer will not take any more messages after it took one and until it send an ack to AMQ. This is a duplication of the work that RabbitMQ has already done for you, and may put you in the mode of "Selective This is important because in situations where multiple Consumers are listening to a Queue, RabbitMQ will prioritise delivery of messages in the same order that the Consumers started listening. Client we can call IModel. However, RabbitMQ will deliver messages to any of the consumers that are available to do work. 0 and higher. subscriptions to a queue´s message stream. But I don't understand why there's two I have a consumer application which needs to consume messages from 2 queues – say regular-jobs-queue and infrequent-jobs-queue. If Consumer #1 was the first Consumer to start, it will be the first to receive messages. It might take a second or two for the subscription data to pass to all processes when starting up. I'm having a problem where I have a queue set up in shared mode and multiple consumers bound to it. Consumer Prefetch Overview . What will happen is that RabbitMQ is going to load balance to your consumers in a round robin matter. basic. To perform what you ask - all receive same message - it must be a Topic, not a Queue. Each consumer has it's own unique message type and this is only for a single service (i. That is really an architecture decision to design a single listener and distribute to its methods according the payload type. Sample code. But QueueBasicConsumer pushes one message at a time. IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. By using multiple consumers, all I get is that when a user is available, all the consumers will perform the same operation, which has to be only once. get doesn't support multiple messages unfortunately as seen in the docs. I know that, I can create two different queues, and use routing key to send different messages to different queue. I checked log client and result was get one message for one consumer, after 10 seconds I get one message for one consumer and so on . This way of distributing messages is called round-robin. Net. Rabbitmq configuration for multiple customers. 0. Unfortunately the channel is not the ideal scope for this - since a single channel may rabbitmq multiple consumers on a queue- only one get the message. Consumers pick any unattended message from queue, so that at a time, more than one consumers are consuming the message from queue? You can add multiple workers to a queue; There can be multiple queues bound to an exchange. enter image description here Multiple consumers on one RabbitMQ queue. Everything is working but not as much as I would, specially regarding consumers performances. 2. channel() channel1. consuming two queues rabbitmq pika python. in order to equally distribute your messages on all the deployed consumers, you need to implement a throttling mechanism on the side of consumers (i suggest you Let's say I have one publisher and 2 consumers. SocketException: An existing connection was forcibly closed by There is one message published by the server to an exchange and there are multiple bindings which cause the distribution to multiple queues. Queue is a single thread on RabbitMQ server. Each queue will get its own binding to the typed message exchange and get its own copy. I have manage to do so with a basic_get : basic_get(queue1) basic_get(queue2) basic_get Implementing multiple competing consumers on the same queue will give you round-robin delivery, allowing the other consumers a chance for success. For queues that have online consumers but no message flow, the value will be 100%: the idea is that any number of consumers can sustain this kind of delivery rate. However, when the first queue is empty, it does go to the next queue, and then Having multiple queues allows you to have multiple consumers, each of which can handle a particular type of message. This is by design in RabbitMQ, when you have multiple consumers on a single queue. This is the problem, in our case. This tells RabbitMQ not to give more than one message to a worker at a time. In the RabbitMQ docs it's called the Work Queue model. See the following diagram. ---> System. Ask Question Asked 7 years, 5 months ago. Well, it isn't possible. queuebind() and another time with yet again When publishing, all consumers should recieve the message once they have been subscribed. I would be grateful if someone could help me solve this problem. py? (However I did check the consumer tags for the two queues in RabbiitMQ Management and there are two different consumer tags for the two queue I'm not sure if that means there's two consumers. Only one will pick a message. 6. RabbitMQ and Python 3: How to consume message from different queues with priority. basicQos(1) or basicqos(0,1,false). NET core consumer service steal messages from the others. In this blog post, we will explore how I'm using Spring AMQP with RabbitMQ. Load 7 more related questions Show fewer related questions Sorted by: Reset to default Know someone who can answer? Share a link to this So initially, receive get's first message M from somewhere in it's towns_queue, then if it detects a delay (in some way) sends again the same message M, and then ACKs the first M, after which it will receive the second MI must be missing something, otherwise the whole thing is running in circles because it's basically one message being forwarded forever. : create if missing) the queues and the exchange, you let both work correctly and you have the guarantee that no messages are lost, You need to use different endpoint names (queues) for each of the services. And multiple instances of a . IO. Each consumer should consume 5 messages at a time (in parallel). Masstransit, RabbitMQ, multiple consumers with multiple instances. This is how I declare the queue: rabbitMQ. Which will not be possible in a distributed Those are two tasks I want to send to a queue having multiple consumers (workers). I am using RabbitMQ with Spring. You may also Multiple Consumer RabbitMQ on one Queue - Java. To define a queue in generic terms, it is a sequential data structure with two primary operations: an item can be enqueued (added) at the tail and dequeued (consumed) from the head. The exchange will decide to which queue to route that message. Currently, there is one worker for the queue which takes one task at a time and until the said task is completed and acknowledged other tasks of the queue won't be picked. I have 2 queues, say q1 and q2, which corresponds to e1 and e2 exchanges with binding key b1 and b2. NET Core 2. You can work with priority queues and consumer priorities. Is that the case? I have a single queue in RabbitMQ where there can be 5-6 tasks queued at a time. At the moment competing instances of the . The routing in RabbitMQ is done by the exchange and binding to those queues. Each server can listen to one or more queues, but each server should process only one task at a time. Is this use case possible with the implementation of the When publishing, all consumers should recieve the message once they have been subscribed. but you need to create a consumer for each queue. Hot I'm looking for clarification on how the UseRateLimit() functionality works in the following situation where we have many consumers sharing the same queue. 1 RabbitMQ and Kubernetes. Each consumer is running in its own process. Share. user. When I start the consumer, I run rabbitmqctl list_queues and I see that the queue has 0 messages. You can have multiple consumers for a single queue. Rabbitmq one queue multiple consumers. NET RabbitMQ client It's perfectly legit that both servers declare the queue and the exchange, and it's usually the preferred approach, when dealing with named queues: usually you want producers and consumers be decoupled, and letting both declare (i. Is this possible? In the configuration found in the docs I only found examples with single queue name for each consumer. Follow edited Dec 26, 2022 at 23:45. Messages are enqueued and dequeued (delivered to consumers) in a (FIFO ("first in, first out") manner. 2 RabbitMq single Consumer with multiple queue. I have a problem with RabbitMQ consumer. creating multiple consumers thus multiple channels will have multiple dispatch threads, but I don't think it provided a better performance to message dispatching since the dispatch should far from enough with one single thread. I want to have one queue with multiple consumers bound to it and then have RabbitMQ send out one message to only one consumer at at time and wait for an ACK before sending out another message to any other consumer. I would also suggest taking a look at RabbitMQ. RabbitMQ's basic. I believe you need kafka's consumer group feature. So, in your case, I hope only one exchange is enough. Each line printed shows, separated by tab characters, the name of the queue subscribed to, the id of the channel process via which the subscription was created and is managed, the consumer tag which uniquely identifies the subscription within a channel, a You can run several consumers in the same process, the number could be a program argument. Each time I start a consumer in a server, I configure it with channel. Then to run multiple consumers to improve the speed. Or don't use a messaging queue and do the processing in a synchronous blocking method, which might sound bad but in many cases and business requirements it is completely valid and sometimes even mission critical. That said, I doubt federated queues would be of any help regarding fairness. So when you subscribe to topic exchange, best way is to declare new queue for each consumer (with any name, or better random generated by rabbit itself) and use target routing key ( cherry. However it doesn't work as expected but at least it didn't break down. 4 Kubernetes RabbitMQ queue mirroring. As I understand if you have multiple consumers on the same queue only one of them will get the message. How to use multithreading with Pika and RabbitMQ to perform requests and responses RPC Messages. 4. At any given time, only 2 consumers should process messages from Q2. There will be multiple queue with multiple queues, but implementation should be done withing single windows services. We are using EventingBasicConsumer in RabbitMQ c# and same queue has initialized with EventingBasicConsumer with different instances. each call to "basic_consume" (or whatever "subscribe" method you are using) is a consumer. We're using RabbitMQ 3. By having multiple consumers listening to the same queue, work can be distributed among them, leading to a more efficient processing system. When using RabbitMQ to handle heavy messages, i need to add more than one consumer for the same publisher and task. All the 10 consumers can process message If the service creates multiple Listeners/Consumers for same queue on a direct exchange below mechanism is applicable: By default, RabbitMQ will send each message to the next consumer, in sequence. See tutorials 3 and 4 and please post You can add multiple workers to a queue; There can be multiple queues bound to an exchange. Unless you absolutely need DTC, RabbitMQ is a much more robust messaging platform. get at the very same time. Please refer this tutorial from RabbitMQ for more info. All is good. You only want to read from the queue when you're ready - so spin up a thread that can spawn the external process and watch it, then fetch the next message from the queue when the process is done. environment: python, pika, RabbitMQ. They will be guaranteed not to share messages (Rabbit will round-robin the messages among the currently-connected consumers) and it's heavily optimized for that exact usage pattern. I need this to be parallel, however, I can't seem to figure out how. As a workaround I can suggest you to delegate the logic from a single @RabbitListener class to those business services: @RabbitListener(queues = "foo") public But I tried to make the single-consumer-multiple-queue structure and it actually works. Hot Network Questions As an adverb, which word’s more idiomatic: “clear” or “clearly”?. Use the basicQos method with the prefetchCount = 1 setting. It just It is possible to a single published message to be routed to more than one queue and eventually delivered to more than one consumer. Commented Jun 7, 2019 at 7:34. there is not way to listen to all queues automatically. consume which will push the messages to the client avoiding multiple round trips. . The easiest way to do this is to use a fanout exchange. The problem is because we have several consumers to treate this type of messages it is possible to have consumer 1 that finish after consumer 2. Consumer code below I want to publish message on RabbitMQ which will be processed by RabbitMQ consumer. My thought: Server A. But I would like to have two consumers on one Queue, and somehow bind Consumer with type of message. I am working with Python, RabbitMQ and Pika. Is it possible for the queue to retain data until after a RabbitMQ offers robust features for message queuing and routing, making it a popular choice for building scalable and reliable systems. RabbitMQ will round-robin the messages to the consumers, but only one consumer will receive the message from the queue. Question are: 1. Receive multiple amqp queues in python / pika. In combination with low prefetch counts, it could be possible to Python program running a single queue with multiple consumers I'm looking for the when the queue receives the multiple messages( ex: 10 messages), Is there any way that multiple consumers(ex: 5 . Each user has a counter to record how many messages has been sent in a period time, if this value is large, the messages published by the user will For a minimal example, imagine two deployments: A RabbitMQ deployment with one pod, and a "Log" deployment with several pods, each running an instance of the same "Log" microservice. I want to run consumer functions in parallel, say c1 and c2 which will listen to q1 and q2 respectively. To set up RabbitMQ for parallel processing, you need to define your queues and ensure that you have multiple consumers ready to process messages. I believe something similar exists in RabbitMQ. I have a Windows service that starts and registers to monitor two different RabbitMQ queues. Viewed 7k times 3 . It doesn't look at the number of unacknowledged messages for a consumer. On average every consumer will get the same number of messages. The problem is that when there is some data already present in the first queue, it consumes the first queue and never goes to consume the second queue. basic_qos(prefetch_count=1) so that only one tasks is processed for the respective queue. Note that consumer capacity is merely a hint. Applications can subscribe to have RabbitMQ push enqueued messages (deliveries) to them. Using that exchange, and one consumer per queue, we can achieve message order with multiple consumers. In amqp, if you need the same message to be received by multiple consumers, you'd need need multiple queues. I have a somewhat unique use case with RabbitMQ and I'm not sure how to go about solving the problem. Expexted Behaviour consumer1: message1 xxxxxxxx message3 xxxxxxxx consumer2: xxxxxxxx message2 xxxxxxxx message4 I have a problem with RabbitMQ consumer. Running RabbitMQ with multiple consumers violates FIFO principle of queue. There are 3-5 workers, which process data from a queue, and occasionally one worker needs to send a message to all workers. This article has a good summary of its features. Or, in other words, don't dispatch a new message to a worker until it has processed and acknowledged the previous one. 1. When I try to get it to listen to both queues, only the 2nd listener works. Most of the tutorials from RabbitMQ and across the web suggest to register multiple consumers for that task (Although most of them opens a new process for each consumer in a new shell, and mine would all go under the same application). Similar to this question, we have FIFO queues and the messages must be processed in order. Every consumer can process Application overview: There can be multiple dynamic queues created. So, you might need to revise your logic. Hot Network Questions How heavy was the In RabbitMQ, we can have multiple consumers listening from one queue. Can we use one subscriber for several queues. It is possible to a single published message to be routed to more than one queue and eventually delivered to more than one consumer. The issue you have is that you're not naming your queue on the service side. {"The AMQP operation was interrupted: AMQP close-reason, initiated by Library, code=541, text=\"Unexpected Exception\", classId=0, methodId=0, cause=System. Once that message has been processed successfully, RabbitMq single Consumer with multiple queue. In RabbitMQ, the producer always sends the message to an exchange. I have multiple consumers and queues. In other words, if you have 3 consumers and you send 3 messages to the queue, each one of those consumers will likely get 1 of the messages. If you want to load balance at the consumer side, you have the above said two options. If there are any messages in ‘infrequent-jobs-queue’ I want to consume those before consuming messages from ‘regular-jobs-queue’. Every consumer can process I am trying to create a consumer that would subscribe to multiple queues, and then process messages as they arrive. My problem: I created 10 consumer and add them into the queue. rabbitmq multiple consumers on a queue- only one get the message. If at least two consumers at the same time can get the same message? I have a RabbitMQ broker with multiple queues set up. qos method to make it possible to limit the number of unacknowledged messages on a channel (or connection) when consuming (aka "prefetch count"). queueDeclare(QUEUE_NAME, true, false, false, null); This is how the Declare a queue with some name; Bind that queue to your topic with your desired routing key pattern; Create multiple consumers and have them listen to that same queue. starball. "User 1 Exchange") and finally there is last binding from user specific It is obvious in a round-robin scenario. My question is, as RabbitMQ does its own Thread Management etc, what is the best approach to create multiple consumers picking messages of the same queue? Looking at this basic example of a simple consumer: So far for a single queue in RabbitMQ I have used a single channel But now I have multiple queues created dynamically, so do I have to create a new channel for each queue or one channel can be to receive/send messages from/to different queues? # consuming for ch in items: channel1 = rconn. The issue is that it appears that rabbitmq is serializing the messages, that is, only one consumer at a time is able to run. Specifically see On the other side I have some consumers on the same queue, which ideally should work in parallel. – Jing Zhu. Here is the example: Instance A, creates a new session of RabbitMQ and initialize the event consumer for a queue name (lets say, queuename: ABC) Is there is a way by which we can restrict RabbitMQ Queue to dispatch only a fixed number of messages from the Queue to the consumers? I have 2 Queues Q1 and Q2 and 10 consumers. Hot Network Questions As an adverb, which word’s more idiomatic: “clear” or “clearly”? Multiple Consumer RabbitMQ on one Queue - Java. Hot Network Questions Finding corners where multiple polygons meet in Multiple Consumer RabbitMQ on one Queue - Java. there's nothing wrong with that. I've searched StackOverflow and I don't think the other issues around multiple consumers match what I am trying. Using RabbitMQ - Multiple Producer and Multiple Consumers. Change you publishing app to send to amq. @Noseratio - no I am not asking about single consumer multiple queue. Hot Network Questions Is it a crime to testify under oath with something that is strictly speaking true, but only strictly? Strange Shading Artifacts Didactic tool to play with deterministic and nondeterministic I have one . created ) to bind those Multiple Consumer RabbitMQ on one Queue - Java. the producer specifies the exchange through which the message is published. Support for multiple-consumer queues is a Message Queue feature (the JMS specification defines messaging behavior in the case of only one consumer accessing a queue). If you need all consumers to receive all messages, then you need to change your configuration so that each consumer has it's own queue. Priorities of consumers on different queues aren't much better but at least I can recall some cases where it made some sense. BTW: there is nothing specific about Docker or I have a question about RabbitMQ queue. acks are asynchronous so your client won't be waiting for the server to respond. Multiple consumer in rabbitmq for multiple queue. My consumer machine is a multi core machine (preferably worker role on azure). We want competing consumers from different machines for redundancy and performance reasons, but only one consumer on one machine should handle a message for a given queue at a time. If I create a certain queue for each employee, how can I subscribe the consumer for greater then one queue? I can send messages in the one queue with the different routing keys (EmployeeID). Each message is being sent to one queue, and the consumer can ack it; however, if there are multiple consumers for the same message, it made sense to me that really, each queue (and each consumer bound to it) has its own message to the consumer, each of which must be acknowledged. Your problem is "thousands of msgs from one user will block other users", I think the solution is use Priority Queue. How to scale up parallel consumers in microservices. Multiple consumers on one queue is useful when you want to divide the load of processing the messages between multiple receivers, but if you want the messages to reach a specific endpoint, create a queue dedicated to that endpoint. Unfortunately the channel is not the ideal scope for this - since a single channel may I'm having a problem where I have a queue set up in shared mode and multiple consumers bound to it. So I want this command to be run on ALL the worker/listeners. Consumer code below rabbitmq multiple consumers on a queue- only one get the message. Queue on a Direct Exchange with multiple consumers is best for this scenario. If don't set it, one consumer can consume all messages on queue and no time to get messages by other consumers, so you can set it by using channel. Messaging brokers receive messages from I am working on a system where a single queue needs to be accessed by multiple consumers for different micro-services. I have multiple workers running on separate vm's that pick up messages in a round robin fashion. I want to publish message on RabbitMQ which will be processed by RabbitMQ consumer. queue_declare(queue=itm) Consumer Prefetch Overview . work well. no competing consumers / distributed processing). But RabbitMQ will make a best-effort. RabbitMQ : Dispatch fixed messages from Queue for multiple consumers. How to have multiple competing consumers for For a minimal example, imagine two deployments: A RabbitMQ deployment with one pod, and a "Log" deployment with several pods, each running an instance of the same "Log" microservice. Sockets. So I doubt the my colleague's idea for the initialization of Sender. I have a Queue that has some 100 messages already. For example, in Apache RabbitMQ. You should generally* avoid direct thread programming in favor of the Task Parallel Library and concurrent collections built into . So instead of writing multiple windows services for each queue consumer, i would like to write single windows services which will listen multiple queues and Multiple consumers on one queue is useful when you want to divide the load of processing the messages between multiple receivers, but if you want the messages to reach a specific endpoint, create a queue dedicated to that endpoint. So: you have a publisher that sends a message to an exchange; then each of your service creates a queue with a random name, and binds it to the exchange; Each Today, the Server A hang at the function amqp_queue_declare in Sender module during test, but it works well after restarting RabbitMQ. Meantime, there is an another web service called ServiceB which is implemented for consuming the messages from the RabbitMQ same queue in an interval of 10 seconds time period. Now I need to do a modification and I want to have a single consumer for two of the queues. AMQP 0-9-1 specifies the basic. RabbitMQ Load Balancing Across Multiple Consumers with Multiple Threads. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company In rabbitmq, if multiple consumers use the same queue - message delivered to that queue is always dispatched in round-robin manner, no matter what. The queue for specific routing key is for specific consumer. direct RabbitMQ has a plugin for consistent hash exchange. bpytjgk zfjhpb phdlbq bbwwv vpicdi gagy ekcvp lsivri xgq tdrfoz