Replication Connection Thread States The thread is executing a  LOAD DATA  statement and is appending the data to a temporary file containing the data from which the replica reads rows. The thread is executing a  LOAD DATA  statement and is creating a temporary file containing the data from which the replica reads rows. This state can only be encountered if the original  LOAD DATA statement was logged by a source running a version of MySQL lower than MySQL 5.0.3. The thread has read an event from the relay log so that the event can be processed. The thread has processed all events in the relay log files, and is now waiting for the I/O thread to write new events to the relay log. Using the multithreaded replica ( slave_parallel_workers  is greater than 1), one of the replica worker threads is waiting for an event from the coordinator thread. A very brief state that occurs as the thread is stopping. This waiting action occurs when the total size of events being processed by Workers exceeds the size of the  slave_pending_jobs_size_max  system variable. The Coordinator resumes scheduling when the size drops below this limit. This state occurs only when  slave_parallel_workers  is set greater than 0. The initial state before  Reading event from the relay log . The SQL thread has read an event but is waiting for the replica delay to lapse. This delay is set with the SOURCE_DELAY  |  MASTER_DELAY  option of the  CHANGE REPLICATION SOURCE TO  statement (from MySQL 8.0.23) or  CHANGE MASTER TO  statement (before MySQL 8.0.23). The  Info  column for the SQL thread may also show the text of a statement. This indicates that the thread has read an event from the relay log, extracted the statement from it, and may be executing it. These thread states occur on a replica server but are associated with connection threads, not with the I/O or SQL threads. The thread is processing a  CHANGE REPLICATION SOURCE TO  statement (from MySQL 8.0.23) or CHANGE MASTER TO  statement (before MySQL 8.0.23). •  Changing master 1856 8.14.7 Replication Connection Thread States •  Waiting until MASTER_DELAY seconds after master executed event •  Waiting for the next event in relay log •  Waiting for Slave Workers to free pending events •  Waiting for slave mutex on exit •  Waiting for an event from Coordinator •  Slave has read all relay log; waiting for more updates •  Reading event from the relay log •  Making temporary file (create) before replaying LOAD DATA INFILE