消息存储流程
默认方法为org.apache.rocketmq.store.DefaultMessageStore中的putMessage(MessageExtBrokerInner msg)方法
1、检查是否可写入消息
2、检查topic和消息属性长度是否合法
3、写入消息
4、设置写入时长
5、判断写入结果
6、返回结果
@Override
public PutMessageResult putMessage(MessageExtBrokerInner msg) {
//检查是否可写入消息
PutMessageStatus checkStoreStatus = this.checkStoreStatus();
if (checkStoreStatus != PutMessageStatus.PUT_OK) {
return new PutMessageResult(checkStoreStatus, null);
}
//检查topic和消息属性长度是否合法
PutMessageStatus msgCheckStatus = this.checkMessage(msg);
if (msgCheckStatus == PutMessageStatus.MESSAGE_ILLEGAL) {
return new PutMessageResult(msgCheckStatus, null);
}
//写入消息
long beginTime = this.getSystemClock().now();
PutMessageResult result = this.commitLog.putMessage(msg);
long elapsedTime = this.getSystemClock().now() - beginTime;
//判断是否超时
if (elapsedTime > 500) {
log.warn("not in lock elapsed time(ms)={}, bodyLength={}", elapsedTime, msg.getBody().length);
}
//设置写入时长
this.storeStatsService.setPutMessageEntireTimeMax(elapsedTime);
//判断写入结果
if (null == result || !result.isOk()) {
this.storeStatsService.getPutMessageFailedTimes().incrementAndGet();
}
//返回结果
return result;
}
检查是否可写入消息
private PutMessageStatus checkStoreStatus() {
//判断broker是否停止工作
if (this.shutdown) {
log.warn("message store has shutdown, so putMessage is forbidden");
return PutMessageStatus.SERVICE_NOT_AVAILABLE;
}
//判断是否是slave节点
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
long value = this.printTimes.getAndIncrement();
if ((value % 50000) == 0) {
log.warn("message store has shutdown, so putMessage is forbidden");
}
return PutMessageStatus.SERVICE_NOT_AVAILABLE;
}
//判断是否拥有写权限
if (!this.runningFlags.isWriteable()) {
long value = this.printTimes.getAndIncrement();
if ((value % 50000) == 0) {
log.warn("message store has shutdown, so putMessage is forbidden");
}
return PutMessageStatus.SERVICE_NOT_AVAILABLE;
} else {
this.printTimes.set(0);
}
if (this.isOSPageCacheBusy()) {
return PutMessageStatus.OS_PAGECACHE_BUSY;
}
return PutMessageStatus.PUT_OK;
}
检查topic和消息属性长度是否合法
private PutMessageStatus checkMessage(MessageExtBrokerInner msg) {
//检查topic长度不能超过127
if (msg.getTopic().length() > Byte.MAX_VALUE) {
log.warn("putMessage message topic length too long " + msg.getTopic().length());
return PutMessageStatus.MESSAGE_ILLEGAL;
}
//消息属性长度不能超过32767个字符
if (msg.getPropertiesString() != null && msg.getPropertiesString().length() > Short.MAX_VALUE) {
log.warn("putMessage message properties length too long " + msg.getPropertiesString().length());
return PutMessageStatus.MESSAGE_ILLEGAL;
}
return PutMessageStatus.PUT_OK;
}
写入消息
public PutMessageResult putMessage(final MessageExtBrokerInner msg) {
// Set the storage time
msg.setStoreTimestamp(System.currentTimeMillis());
// Set the message body BODY CRC (consider the most appropriate setting
// on the client)
msg.setBodyCRC(UtilAll.crc32(msg.getBody()));
// Back to Results
AppendMessageResult result = null;
StoreStatsService storeStatsService = this.defaultMessageStore.getStoreStatsService();
String topic = msg.getTopic();
int queueId = msg.getQueueId();
//判断事务类型
final int tranType = MessageSysFlag.getTransactionValue(msg.getSysFlag());
if (tranType == MessageSysFlag.TRANSACTION_NOT_TYPE
|| tranType == MessageSysFlag.TRANSACTION_COMMIT_TYPE) {
// Delay Delivery，如果消息延迟级别大于0
if (msg.getDelayTimeLevel() > 0) {
if (msg.getDelayTimeLevel() > this.defaultMessageStore.getScheduleMessageService().getMaxDelayLevel()) {
msg.setDelayTimeLevel(this.defaultMessageStore.getScheduleMessageService().getMaxDelayLevel());
}
//使用延迟消息主题RMQ_SYS_SCHEDULE_TOPIC
topic = TopicValidator.RMQ_SYS_SCHEDULE_TOPIC;
queueId = ScheduleMessageService.delayLevel2QueueId(msg.getDelayTimeLevel());
// Backup real topic, queueId
MessageAccessor.putProperty(msg, MessageConst.PROPERTY_REAL_TOPIC, msg.getTopic());
MessageAccessor.putProperty(msg, MessageConst.PROPERTY_REAL_QUEUE_ID, String.valueOf(msg.getQueueId()));
msg.setPropertiesString(MessageDecoder.messageProperties2String(msg.getProperties()));
//将消息的原topic名称和原队列ID存入属性中
msg.setTopic(topic);
msg.setQueueId(queueId);
}
}
InetSocketAddress bornSocketAddress = (InetSocketAddress) msg.getBornHost();
if (bornSocketAddress.getAddress() instanceof Inet6Address) {
msg.setBornHostV6Flag();
}
InetSocketAddress storeSocketAddress = (InetSocketAddress) msg.getStoreHost();
if (storeSocketAddress.getAddress() instanceof Inet6Address) {
msg.setStoreHostAddressV6Flag();
}
long elapsedTimeInLock = 0;
MappedFile unlockMappedFile = null;
//mappedFileQueue相当于CommitLog文件夹，MappedFile则是文件夹下的单个文件
//获取当前的commitlog文件
MappedFile mappedFile = this.mappedFileQueue.getLastMappedFile();
//在写入commitlog前，先获取写入锁，说明消息存储是串行的
putMessageLock.lock(); //spin or ReentrantLock ,depending on store config
try {
long beginLockTimestamp = this.defaultMessageStore.getSystemClock().now();
this.beginTimeInLock = beginLockTimestamp;
// Here settings are stored timestamp, in order to ensure an orderly
// global，设置消息存储的开始时间
msg.setStoreTimestamp(beginLockTimestamp);
if (null == mappedFile || mappedFile.isFull()) {
//如果文件不存在或者文件已满，则新创建一个文件
mappedFile = this.mappedFileQueue.getLastMappedFile(0); // Mark: NewFile may be cause noise
}
if (null == mappedFile) {
//判断文件是否创建成功
log.error("create mapped file1 error, topic: " + msg.getTopic() + " clientAddr: " + msg.getBornHostString());
beginTimeInLock = 0;
return new PutMessageResult(PutMessageStatus.CREATE_MAPEDFILE_FAILED, null);
}
//写入消息
result = mappedFile.appendMessage(msg, this.appendMessageCallback);
//判断消息存储结果
switch (result.getStatus()) {
case PUT_OK:
break;
case END_OF_FILE:
unlockMappedFile = mappedFile;
// Create a new file, re-write the message
mappedFile = this.mappedFileQueue.getLastMappedFile(0);
if (null == mappedFile) {
// XXX: warn and notify me
log.error("create mapped file2 error, topic: " + msg.getTopic() + " clientAddr: " + msg.getBornHostString());
beginTimeInLock = 0;
return new PutMessageResult(PutMessageStatus.CREATE_MAPEDFILE_FAILED, result);
}
result = mappedFile.appendMessage(msg, this.appendMessageCallback);
break;
case MESSAGE_SIZE_EXCEEDED:
case PROPERTIES_SIZE_EXCEEDED:
beginTimeInLock = 0;
return new PutMessageResult(PutMessageStatus.MESSAGE_ILLEGAL, result);
case UNKNOWN_ERROR:
beginTimeInLock = 0;
return new PutMessageResult(PutMessageStatus.UNKNOWN_ERROR, result);
default:
beginTimeInLock = 0;
return new PutMessageResult(PutMessageStatus.UNKNOWN_ERROR, result);
}
elapsedTimeInLock = this.defaultMessageStore.getSystemClock().now() - beginLockTimestamp;
beginTimeInLock = 0;
} finally {
putMessageLock.unlock();
}
if (elapsedTimeInLock > 500) {
log.warn("[NOTIFYME]putMessage in lock cost time(ms)={}, bodyLength={} AppendMessageResult={}", elapsedTimeInLock, msg.getBody().length, result);
}
if (null != unlockMappedFile && this.defaultMessageStore.getMessageStoreConfig().isWarmMapedFileEnable()) {
this.defaultMessageStore.unlockMappedFile(unlockMappedFile);
}
PutMessageResult putMessageResult = new PutMessageResult(PutMessageStatus.PUT_OK, result);
// Statistics
storeStatsService.getSinglePutMessageTopicTimesTotal(msg.getTopic()).incrementAndGet();
storeStatsService.getSinglePutMessageTopicSizeTotal(topic).addAndGet(result.getWroteBytes());
handleDiskFlush(result, putMessageResult, msg);
handleHA(result, putMessageResult, msg);
return putMessageResult;
}
public AppendMessageResult appendMessagesInner(final MessageExt messageExt, final AppendMessageCallback cb) {
assert messageExt != null;
assert cb != null;
//获取当前写指针
int currentPos = this.wrotePosition.get();
//检查当前写指针是不是小于文件最大容量大小
if (currentPos < this.fileSize) {
//通过slice方法创建一个与原ByteBuffer共享的内存区
ByteBuffer byteBuffer = writeBuffer != null ? writeBuffer.slice() : this.mappedByteBuffer.slice();
byteBuffer.position(currentPos);//设置position为当前指针
AppendMessageResult result;
if (messageExt instanceof MessageExtBrokerInner) {
//把消息内容存储到ByteBuffer
result = cb.doAppend(this.getFileFromOffset(), byteBuffer, this.fileSize - currentPos, (MessageExtBrokerInner) messageExt);
} else if (messageExt instanceof MessageExtBatch) {
result = cb.doAppend(this.getFileFromOffset(), byteBuffer, this.fileSize - currentPos, (MessageExtBatch) messageExt);
} else {
return new AppendMessageResult(AppendMessageStatus.UNKNOWN_ERROR);
}
this.wrotePosition.addAndGet(result.getWroteBytes());
this.storeTimestamp = result.getStoreTimestamp();
return result;
}
log.error("MappedFile.appendMessage return null, wrotePosition: {} fileSize: {}", currentPos, this.fileSize);
return new AppendMessageResult(AppendMessageStatus.UNKNOWN_ERROR);
}