These views summarize stages, grouped by user. By default, rows are sorted by user and descending total stage latency.
The user_summary_by_stages and x$user_summary_by_stages views have these columns:
user
The client user name. Rows for which the USER column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background.
event_name
The stage event name.
total
The total number of occurrences of the stage event for the user.
total_latency
The total wait time of timed occurrences of the stage event for the user.
avg_latency
The average wait time per timed occurrence of the stage event for the user.