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MySQL 8.0 Reference Manual  /  ...  /  The user_summary_by_file_io and x$user_summary_by_file_io Views

30.4.3.42 The user_summary_by_file_io and x$user_summary_by_file_io Views

These views summarize file I/O, grouped by user. By default, rows are sorted by descending total file I/O latency.

The user_summary_by_file_io and x$user_summary_by_file_io 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.

  • ios

    The total number of file I/O events for the user.

  • io_latency

    The total wait time of timed file I/O events for the user.