Rabbitmq priority 优先级
来源:互联网 发布:域名向谁注册 编辑:程序博客网 时间:2024/05/01 00:35
Rabbitmq priority 优先级
顾名思义,具有更高优先级的队列具有较高的优先权,优先级高的消息具备优先被消费的特权。
RabbitMQ has priority queue implementation in the core as of version 3.5.0.
在系统应用中会根据业务的优先级来决定哪些内容优先被解决,那么在RabbitMQ 3.5+版本中支持了队列优先级和消息优先级,那么这里就尝试下该功能。
在rabbitmq webUI界面中,add queue是通过添加Arguments或者是在代码中添加效果是一样的,取值范围在0~255之间:
The message priority field is defined as an unsigned byte, so in practice priorities should be between 0 and 255.
具体代码如下:
生产者:
public class NewTask { private final static String hostname = "192.168.1.137"; //队列名称 private final static String QUEUE_NAME = "workqueue"; public static void main(String[] args) throws IOException, TimeoutException { //创建连接和频道 ConnectionFactory factory = new ConnectionFactory(); factory.setHost(hostname); Connection connection = factory.newConnection(); Channel channel = connection.createChannel(); try { Map<String,Object> param = new HashMap<String,Object>(); param.put("x-max-priority", 10); channel.queueDeclare(QUEUE_NAME, false, false, true, param); //send message with priority for(int i=0;i<10;i++) { AMQP.BasicProperties.Builder builder = new AMQP.BasicProperties.Builder(); if(i==9 || i==3 || i==5) builder.priority(5); AMQP.BasicProperties properties = builder.build(); channel.basicPublish("",QUEUE_NAME,properties,("messages-"+i).getBytes()); } }catch (Exception e){ e.printStackTrace(); }finally { channel.close(); connection.close(); } }}
消费者:
public class Worker1 { private final static String hostname = "192.168.1.137"; //队列名称 private final static String QUEUE_NAME = "workqueue"; public static void main(String[] argv) throws java.io.IOException, java.lang.InterruptedException, TimeoutException { ConnectionFactory factory = new ConnectionFactory(); factory.setHost(hostname); Connection connection = factory.newConnection(); Channel channel = connection.createChannel(); QueueingConsumer consumer = new QueueingConsumer(channel); channel.basicConsume(QUEUE_NAME, false, consumer); while (true) { QueueingConsumer.Delivery delivery = consumer.nextDelivery(); String msg = new String(delivery.getBody()); System.out.println(msg); channel.basicAck(delivery.getEnvelope().getDeliveryTag(),false); } }}
代码中判断i==3,i==5,i==9这三个消息的权重相等5且高于其他消息,理应提前被处理,代码运行结果为:
测试结果:
查看运行结果可以验证优先级队列的作用。
当然,在消费端速度大于生产端速度,且broker中没有消息堆积的话,对发送的消息设置优先级也没什么实际意义,因为发送端刚发送完一条消息就被消费端消费了,那么就相当于broker至多只有一条消息,那么对于单条消息来说优先级是没有什么意义的。
参考链接
1、https://www.rabbitmq.com/priority.html
2、http://zkread.com/article/1246857.html
1 0
- Rabbitmq priority 优先级
- Rabbitmq priority 优先级
- Priority Inversion:优先级反转
- 优先级队列 priority queue
- Priority Queue 优先级队列
- 优先级队列(Priority Queue)
- Priority Inversion - 优先级翻转
- java 线程的优先级Priority
- Priority Queues优先级队列详解
- 优先级倒置(Priority inversion)
- android 改变线程优先级Change Thread Priority
- 说说优先级倒置(Priority inversion)
- 改变线程优先级Change Thread Priority
- 程序执行优先级--Priority 与 Nice 值
- 优先级队列(priority——queue)
- 关于SB的Layout优先级(priority)
- 多线程中的join(),yield()与优先级Priority
- [STL]Priority Queue (eden)优先级队列
- 运用反射获取自定义注解信息
- python并发库:concurrent.futures的使用
- 你真的会玩SQL吗?内连接、外连接
- Java定时器
- redis 事务(MULTI 、 EXEC 、 DISCARD 和 WATCH )
- Rabbitmq priority 优先级
- Ubuntu 输入法不显示(无法选择)解决
- stl algorithm merge
- Funny Car Racing CSU
- Remove Duplicates from Sorted Array (java版)
- 深入理解MySQL的外连接、内连接、交叉连接
- Numpy中的数组花式索引
- 剑指offer-面试题 9 斐波那契数列
- Android用户引导页实现,圆点实现动画效果