RocketMQ之NameServer学习笔记
org.apache.rocketmq.namesrv.NamesrvController
NameserController,NameServer的核心控制类。
1.1 NamesrvConfig
NamesrvConfig,主要指定nameserver的相关配置目录属性
1）kvConfigPath(kvConfig.json)
2）mqhome/namesrv/namesrv.properties
3）orderMessageEnable，是否开启顺序消息功能，默认为false
1.2 ScheduledExecutorService scheduledExecutorService
private final ScheduledExecutorService scheduledExecutorService = Executors.newSingleThreadScheduledExecutor(new ThreadFactoryIm pl("NSScheduledThread"));
NameServer 定时任务执行线程池，一个线程，默认定时执行两个任务：
任务1、每隔10s扫描broker,维护当前存活的Broker信息
任务2、每隔10s打印KVConfig信息。
1.3 KVConfigManager
读取或变更NameServer的配置属性，加载NamesrvConfig中配置的配置文件到内存，此类一个亮点就是使用轻量级的非线程安全容器，再结合读写锁对资源读写进行保护。尽最大程度提高线程的并发度。
1.4 RouteInfoManager
NameServer数据的载体，记录Broker,Topic等信息。
//NameServer 与 Broker 空闲时长，默认2分钟，在2分钟内Nameserver没有收到Broker的心跳包，则关闭该连接。
private final static long BROKER_CHANNEL_EXPIRED_TIME = 1000 * 60 * 2;
//读写锁，用来保护非线程安全容器HashMap
private final ReadWriteLock lock = new ReentrantReadWriteLock();
//topicQueueTable，主题与队列关系，记录一个主题的队列分布在哪些Broker上，每个Broker上存在该主题的队列个数
private final HashMap<String/* topic */, List<QueueData>> topicQueueTable;
//brokerAddrTable,所有Broker信息，使用brokerName当key,BrokerData信息描述每一个broker信息。
private final HashMap<String/* brokerName */, BrokerData> brokerAddrTable;
//clusterAddrTable，broker集群信息，每个集群包含哪些Broker
private final HashMap<String/* clusterName */, Set<String/* brokerName */>> clusterAddrTable;
//brokerLiveTable，当前存活的Broker,该信息不是实时的，NameServer每10S扫描一次所有的broker,根据心跳包的时间得知broker的状态，该机制也是导致当一个master Down掉后，消息生产者无法感知，可能继续向Down掉的Master发送消息，导致失败
private final HashMap<String/* brokerAddr */, BrokerLiveInfo> brokerLiveTable;
private final HashMap<String/* brokerAddr */, List<String>/* Filter Server */> filterServerTable;
/**
* Broker信息；key为brokerName，value为BrokerData
*/
private final HashMap<String/* brokerName */, BrokerData> brokerAddrTable;
public class BrokerData implements Comparable<BrokerData> {
/**
* Cluster名称
*/
private String cluster;
/**
* broker名称
*/
private String brokerName;
/**
* 0->ip:port
*/
private HashMap<Long/* brokerId */, String/* broker address */> brokerAddrs;
}
- 注册topic信息topicQueueTable
/**
* 消息队列路由信息；key为topic，value为QueueData
*/
private final HashMap<String/* topic */, List<QueueData>> topicQueueTable;
public class QueueData implements Comparable<QueueData> {
/**
* Broker名称
*/
private String brokerName;
/**
* 读队列个数，默认4个
*/
private int readQueueNums;
/**
* 写队列个数，默认4个
*/
private int writeQueueNums;
/**
* 队列权限
*/
private int perm;
/**
* 配置的,同步复制还是异步复制标记,对应TopicConfig.topicSysFlag
*
*/
private int topicSynFlag;
}
/**
* Broker状态信息，NameServer每次收到心跳包会替换该信息，每隔30秒更新一次
* brokerAddr: ip:port->{}
*/
private final HashMap<String/* brokerAddr */, BrokerLiveInfo> brokerLiveTable;
class BrokerLiveInfo {
/**
* 存储上次收到心跳包的时间,每隔30秒更新一次
*/
private long lastUpdateTimestamp;
private DataVersion dataVersion;
private Channel channel;
private String haServerAddr;
}
- NamesrvStartup.java 启动入口类，NameServer 启动默认端口9876
nettyServerConfig.setListenPort(9876)
- 每10秒钟扫描一次，移除失效的broker，同时删除缓存元数据信息
//初始化NameServer
boolean initResult = controller.initialize();
public boolean initialize() {
//加载KV配置
this.kvConfigManager.load();
this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.brokerHousekeepingService);
this.remotingExecutor =
Executors.newFixedThreadPool(nettyServerConfig.getServerWorkerThreads(), new ThreadFactoryImpl("RemotingExecutorThread_"));
this.registerProcessor();
//每10秒钟扫描一次，移除失效的broker
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
NamesrvController.this.routeInfoManager.scanNotActiveBroker();
}
}, 5, 10, TimeUnit.SECONDS);
//每隔10秒钟打印一次KV配置信息
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
NamesrvController.this.kvConfigManager.printAllPeriodically();
}
}, 1, 10, TimeUnit.MINUTES);
return true;
}
- 失效时间为2分钟，即：Broker在2分钟内未上报心跳会被移除
/**
* 失效时间为2分钟，即：Broker在2分钟内未上报心跳会被移除
*/
public void scanNotActiveBroker() {
Iterator<Entry<String, BrokerLiveInfo>> it = this.brokerLiveTable.entrySet().iterator();
while (it.hasNext()) {
Entry<String, BrokerLiveInfo> next = it.next();
long last = next.getValue().getLastUpdateTimestamp();
if ((last + BROKER_CHANNEL_EXPIRED_TIME) < System.currentTimeMillis()) {
RemotingUtil.closeChannel(next.getValue().getChannel());
it.remove();
log.warn("The broker channel expired, {} {}ms", next.getKey(), BROKER_CHANNEL_EXPIRED_TIME);
this.onChannelDestroy(next.getKey(), next.getValue().getChannel());
}
}
}
private final static long BROKER_CHANNEL_EXPIRED_TIME = 1000 * 60 * 2;
2.DefaultRequestProcessor
- 用于响应客户端、Broker的请求。主要向NameServer发送心跳包、获取Cluster、Broker、Topic元数据信息。
- 调用链：
在NameServer启动时注册，NamesrvController.initialize()->registerProcessor()
public RemotingCommand processRequest(ChannelHandlerContext ctx, RemotingCommand request) throws RemotingCommandException {
if (log.isDebugEnabled()) {
log.debug("receive request, {} {} {}",
request.getCode(),
RemotingHelper.parseChannelRemoteAddr(ctx.channel()),
request);
}
switch (request.getCode()) {
case RequestCode.PUT_KV_CONFIG://增加NameServer配置信息；由DefaultMQAdminExt使用
return this.putKVConfig(ctx, request);
case RequestCode.GET_KV_CONFIG://根据NameSpace和key获取NameServer配置信息；由DefaultMQAdminExt使用
return this.getKVConfig(ctx, request);
case RequestCode.DELETE_KV_CONFIG: //据NameSapce和Key删除NameServerr配置信息
return this.deleteKVConfig(ctx, request);
case RequestCode.REGISTER_BROKER: //注册Broker信息；由BrokerOuterAPI.registerBroker使用，在BrokerController启动时调用
Version brokerVersion = MQVersion.value2Version(request.getVersion());
if (brokerVersion.ordinal() >= MQVersion.Version.V3_0_11.ordinal()) {
return this.registerBrokerWithFilterServer(ctx, request);
} else {
return this.registerBroker(ctx, request);
}
case RequestCode.UNREGISTER_BROKER://移除注销broker信息；由BrokerOuterAPI.unregisterBroker使用，在BrokerController.shutdown时调用
return this.unregisterBroker(ctx, request);
case RequestCode.GET_ROUTEINTO_BY_TOPIC: //获取Topic路由信息 TopicRouteData
return this.getRouteInfoByTopic(ctx, request);
case RequestCode.GET_BROKER_CLUSTER_INFO://获取Cluster及Broker信息
return this.getBrokerClusterInfo(ctx, request);
case RequestCode.WIPE_WRITE_PERM_OF_BROKER: //去除该broker上所有topic的写权限
return this.wipeWritePermOfBroker(ctx, request);
case RequestCode.GET_ALL_TOPIC_LIST_FROM_NAMESERVER: //获取所有的Topic列表
return getAllTopicListFromNameserver(ctx, request);
case RequestCode.DELETE_TOPIC_IN_NAMESRV: //从nameServer中删除topic
return deleteTopicInNamesrv(ctx, request);
case RequestCode.GET_KVLIST_BY_NAMESPACE: //获取配置信息 configTable
return this.getKVListByNamespace(ctx, request);
case RequestCode.GET_TOPICS_BY_CLUSTER: //获取该集群下的所有topic list
return this.getTopicsByCluster(ctx, request);
case RequestCode.GET_SYSTEM_TOPIC_LIST_FROM_NS: // 此处意思为：系统会将集群名称、broker名称作为默认topic创建。现在获取这类topic
return this.getSystemTopicListFromNs(ctx, request);
case RequestCode.GET_UNIT_TOPIC_LIST: //暂无使用
return this.getUnitTopicList(ctx, request);
case RequestCode.GET_HAS_UNIT_SUB_TOPIC_LIST: //暂无使用
return this.getHasUnitSubTopicList(ctx, request);
case RequestCode.GET_HAS_UNIT_SUB_UNUNIT_TOPIC_LIST://暂无使用
return this.getHasUnitSubUnUnitTopicList(ctx, request);
case RequestCode.UPDATE_NAMESRV_CONFIG: //更新properties请求
return this.updateConfig(ctx, request);
case RequestCode.GET_NAMESRV_CONFIG: //获取properties内容
return this.getConfig(ctx, request);
default:
break;
}
return null;
}
注册broker信息
- Broker每隔30秒向所有的NameServer上报Topic注册信息
- Broker调用链
BrokerController.start()->this.registerBrokerAll()->this.brokerOuterAPI.registerBrokerAll()
//每隔30秒向所有的NameServer上报Topic注册信息
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.registerBrokerAll(true, false);
} catch (Throwable e) {
log.error("registerBrokerAll Exception", e);
}
}
}, 1000 * 10, 1000 * 30, TimeUnit.MILLISECONDS);
- 服务端处理主要包括：注册集群信息clusterAddrTable、注册broker信息brokerAddrTable、
注册topic信息topicQueueTable、broker心跳包brokerLiveTable - NameServer处理链
DefaultRequestProcessor->processRequest->RequestCode.REGISTER_BROKER->this.registerBroker->RouteInfoManager.registerBroker()
public RegisterBrokerResult registerBroker(
final String clusterName,
final String brokerAddr,
final String brokerName,
final long brokerId,
final String haServerAddr,
final TopicConfigSerializeWrapper topicConfigWrapper,
final List<String> filterServerList,
final Channel channel) {
RegisterBrokerResult result = new RegisterBrokerResult();
try {
try {
//加写锁，防止并发修改
this.lock.writeLock().lockInterruptibly();
//注册集群信息
Set<String> brokerNames = this.clusterAddrTable.get(clusterName);
if (null == brokerNames) {
brokerNames = new HashSet<String>();
this.clusterAddrTable.put(clusterName, brokerNames);
}
brokerNames.add(brokerName);
boolean registerFirst = false;
//注册broker信息
BrokerData brokerData = this.brokerAddrTable.get(brokerName);
if (null == brokerData) {
registerFirst = true;
brokerData = new BrokerData(clusterName, brokerName, new HashMap<Long, String>());
this.brokerAddrTable.put(brokerName, brokerData);
}
String oldAddr = brokerData.getBrokerAddrs().put(brokerId, brokerAddr);
registerFirst = registerFirst || (null == oldAddr);
//Topic配置变化了；Master Broker第一次注册或者Topic dataVersion不相同时更新路由信息
//有Topic新增时dataVersion会递增
if (null != topicConfigWrapper //
&& MixAll.MASTER_ID == brokerId) {
if (this.isBrokerTopicConfigChanged(brokerAddr, topicConfigWrapper.getDataVersion())//
|| registerFirst) {
ConcurrentMap<String, TopicConfig> tcTable =
topicConfigWrapper.getTopicConfigTable();
if (tcTable != null) {
for (Map.Entry<String, TopicConfig> entry : tcTable.entrySet()) {
this.createAndUpdateQueueData(brokerName, entry.getValue()); //更新topicQueueTable
}
}
}
}
//更新broker心跳信息
BrokerLiveInfo prevBrokerLiveInfo = this.brokerLiveTable.put(brokerAddr,
new BrokerLiveInfo(
System.currentTimeMillis(),
topicConfigWrapper.getDataVersion(),
channel,
haServerAddr));
//新broker注册时会有日志输出
if (null == prevBrokerLiveInfo) {
log.info("new broker registerd, {} HAServer: {}", brokerAddr, haServerAddr);
}
//更新filterServer信息
if (filterServerList != null) {
if (filterServerList.isEmpty()) {
this.filterServerTable.remove(brokerAddr);
} else {
this.filterServerTable.put(brokerAddr, filterServerList);
}
}
//Slave设置MasterAddr和HaServerAddr
if (MixAll.MASTER_ID != brokerId) {
String masterAddr = brokerData.getBrokerAddrs().get(MixAll.MASTER_ID);
if (masterAddr != null) {
BrokerLiveInfo brokerLiveInfo = this.brokerLiveTable.get(masterAddr);
if (brokerLiveInfo != null) {
result.setHaServerAddr(brokerLiveInfo.getHaServerAddr());
result.setMasterAddr(masterAddr);
}
}
}
} finally {
this.lock.writeLock().unlock();
}
} catch (Exception e) {
log.error("registerBroker Exception", e);
}
return result;
}
