RocketMQ原理解析-broker 1. broker的启动

brker的启动

Broker向namesrv注册

1.      获取namesrv的地址列表（是乱序的）

2.      遍历向每个namesrv注册topic的配置信息topicconfig

Topic在broker文件上的存储json格式

“TopicTest”:{

                            “perm”:6,

                            “readQueueNums”:8,

                            “topicFilterType”:”SINGLE_TAG”,

                            “topicName”:”TopicTest”,

                            “writeQueueNums”:8

                   }

 

Namesrv接收Broker注册的topic信息， namesrv只存内存，但是broker有任务定时推送

1.      接收数据向RouteInfoManager注册。

 

 

Broker初始化加载本地配置，配置信息是以json格式存储在本地， rocketmq强依赖fastjson作转换， RocketMq通过ConfigMananger来管理配置加载以及持久化

1.      加载topic配置${user.home}/store/config/topics.json

{

“dataVersion”:{

           “counter”:2,

           “timestatmp”:1393729865073

},

“topicConfigTable”:{

           //根据consumer的group生成的重试topic

           “%RETRY% group_name”:{

                    “perm”:6,

                    “readQueueNums”:1,

                    “topicFilterType”:”SINGLE_TAG”,

                    “topicName”:”%RETRY%group_name”,

                    “writeQueueNums”:1

           },

           “TopicTest”:{

                    “perm”:6,  // 100读权限 , 10写权限   6是110读写权限

                    “readQueueNums”:8,

                    “topicFilterType”:”SINGLE_TAG”,

                    “topicName”:”TopicTest”,

                    “writeQueueNums”:8

           }

}

}

2.      加载消费进度偏移量  ${user.home}/store/config/consumerOffset.json

{

“offsetTable”:{

            “%RETRY% group_name@group_name”:{

0:0 //重试队列消费进度为零

           },      

“TopicTest@ group_name”:{

0:23,1:23,2:22,3:22,4:21,5:18,6:18,7:18

//分组名group_name消费topic为TopicTest的进度为：

// 队列queue=0  消费进度23

// 队列 queue=2  消费进度为22  等等…

           }

}

}

3.      加载消费者订阅关系 ${user.home}/store/config/subscriptionGroup.json

  {

         “dataVersion”:{

                   “counter”:1,

                   “timestatmp”:1393641744664

         },

         “group_name”:{

                            “brokerId”:0,  //0代表这台broker机器为master，若要设为slave值大于0

                            “consumeBroadcastEnable”:true,

                            “consumeEnable”:true,

                            “consumeFromMinEnable”:true,

                            “groupName”:”group_name”,

                            “retryMaxTimes”:5,

                            “retryQueueNums”:1,

                            “whichBrokerWhenConsumeSlowly”:1

                   }

         }

}