2019-07-29 15:19:30 975211 [Warning] Timeout waiting for reply of binlog (file: bin_log.000346, pos: 247856273), semi-sync up to file bin_log.000346, position 247854688.

2019-07-29 15:19:30 975211 [Note] Semi-sync replication switched OFF.

2019-07-29 15:20:32 974875 [Note] Stop semi-sync binlog_dump to slave (server_id: 2)

2019-07-29 15:20:33 974874 [Note] Stop semi-sync binlog_dump to slave (server_id: 3)

2019-07-29 15:20:46 11 [ERROR] Semi-sync slave net_flush() reply failed

2019-07-29 15:20:46 11 [ERROR] Slave I/O: Fatal error: Failed to run 'after_queue_event' hook, Internal MariaDB error code: 1593

2019-07-29 15:20:46 11 [Note] Slave I/O thread exiting, read up to log 'bin_log.000346', position 247948930; GTID position 1-1-146008965

semisynch: Last_IO_Error: Fatal error: Failed to run 'after_queue_event' hook

      Errors when send reply to master should never cause the IO thread

      to stop, because master can fall back to async replication if it

      does not get reply from slave.

      The problem is fixed by deliberately ignoring the return value of

      slaveReply.

     @ plugin/semisync/semisync_slave_plugin.cc

        Deliberately ignore the return value of slaveReply so that errors

        while sending slave reply will not cause the IO thread to stop.