3 Broker
3.1 Broker Role
Broker Role is ASYNC_MASTER, SYNC_MASTER or SLAVE. If you cannot tolerate message missing, we suggest you deploy SYNC_MASTER and attach a SLAVE to it. If you feel ok about missing, but you want the Broker to be always available, you may deploy ASYNC_MASTER with SLAVE. If you just want to make it easy, you may only need a ASYNC_MASTER without SLAVE.
3.2 FlushDiskType
ASYNC_FLUSH is recommended, for SYNC_FLUSH is expensive and will cause too much performance loss. If you want reliability, we recommend you use SYNC_MASTER with SLAVE.
3.3 Broker Configuration
| Parameter name | Default | Description |
|---|---|---|
| listenPort | 10911 | listen port for client |
| namesrvAddr | null | name server address |
| brokerIP1 | InetAddress for network interface | Should be configured if having multiple addresses |
| brokerIP2 | InetAddress for network interface | If configured for the Master broker in the Master/Slave cluster, slave broker will connect to this port for data synchronization |
| brokerName | null | broker name |
| brokerClusterName | DefaultCluster | this broker belongs to which cluster |
| brokerId | 0 | broker id, 0 means master, positive integers mean slave |
| storePathCommitLog | $HOME/store/commitlog/ | file path for commit log |
| storePathConsumerQueue | $HOME/store/consumequeue/ | file path for consume queue |
| mappedFileSizeCommitLog | 1024 1024 1024(1G) | mapped file size for commit log |
| deleteWhen | 04 | When to delete the commitlog which is out of the reserve time |
| fileReserverdTime | 72 | The number of hours to keep a commitlog before deleting it |
| brokerRole | ASYNC_MASTER | SYNC_MASTER/ASYNC_MASTER/SLAVE |
| flushDiskType | ASYNC_FLUSH | {SYNC_FLUSH/ASYNC_FLUSH}. Broker of SYNC_FLUSH mode flushes each message onto disk before acknowledging producer. Broker of ASYNC_FLUSH mode, on the other hand, takes advantage of group-committing, achieving better performance. |