默認情況下,MySQL的復制功能是異步的。master把binlog發送給slave時,這個復制動作就已經完成,master不會驗證slave是否接收完畢(類似于Oracle DataGuard Maximum Performance)。異步復制同時意味著在把數據從一個mysqld實例拷貝到另一個mysqld時有一個延
Multi-channel replication is one of the great feature shipped with MySQL 5.7, With allowed the capability of slave to have many masters, having a channel for each master by which they replicate. Each channel id has a unique “ channel_name ”Multi-Channel