MySQL 9.3 Release Notes
        
        If necessary, you can stop a cloning operation with a
        KILL QUERY
         statement.
      processlist_id
        On the recipient MySQL server instance, you can retrieve the
        processlist identifier (PID) for a cloning operation from the
        PID column of the
        clone_status table.
      
mysql> SELECT * FROM performance_schema.clone_status\G
*************************** 1. row ***************************
             ID: 1
            PID: 8
          STATE: In Progress
     BEGIN_TIME: 2019-07-15 11:58:36.767
       END_TIME: NULL
         SOURCE: LOCAL INSTANCE
    DESTINATION: /path/to/clone_dir/
       ERROR_NO: 0
  ERROR_MESSAGE:
    BINLOG_FILE:
BINLOG_POSITION: 0
  GTID_EXECUTED:
        You can also retrieve the processlist identifier from the
        ID column of the
        INFORMATION_SCHEMA
        PROCESSLIST table, the
        Id column of SHOW
        PROCESSLIST output, or the
        PROCESSLIST_ID column of the Performance
        Schema threads table. These methods
        of obtaining the PID information can be used on the donor or
        recipient MySQL server instance.