8.12.5.4. Replication Master Thread States

The following list shows the most common states you may see in the State column for the master's Binlog Dump thread. If you see no Binlog Dump threads on a master server, this means that replication is not running—that is, that no slaves are currently connected.

Sending binlog event to slave

Binary logs consist of events, where an event is usually an update plus some other information. The thread has read an event from the binary log and is now sending it to the slave.
Finished reading one binlog; switching to next binlog

The thread has finished reading a binary log file and is opening the next one to send to the slave.
Master has sent all binlog to slave; waiting for binlog to be updated

The thread has read all outstanding updates from the binary logs and sent them to the slave. The thread is now idle, waiting for new events to appear in the binary log resulting from new updates occurring on the master.
Waiting to finalize termination

A very brief state that occurs as the thread is stopping.