Current output of SHOW PROCESSLIST for slave processing initial events for LOAD DATA (Create_file, Append_block) is not very descriptive. So sometimes user should guess "What slave thread is doing now ?" The idea is to display "Appending block to temporary file 'xxx'" info for Create_file and Append_block events. We even can put size of this file in this string to show progress. For Exec_load_log_event we could display the complete query. Citing Guilhem: To do this, we just need to call some code of Load_log_event::print(). Redirect the output in a string, and you'll get a beautiful SHOW PROCESSLIST when the slave is executing Exec_load.