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MySQL 8.4 Reference Manual  /  ...  /  The io_global_by_wait_by_latency and x$io_global_by_wait_by_latency Views

30.4.3.14 The io_global_by_wait_by_latency and x$io_global_by_wait_by_latency Views

These views summarize global I/O consumers to display amount of I/O and time waiting for I/O, grouped by event. By default, rows are sorted by descending total latency.

The io_global_by_wait_by_latency and x$io_global_by_wait_by_latency views have these columns:

  • event_name

    The I/O event name, with the wait/io/file/ prefix stripped.

  • total

    The total number of occurrences of the I/O event.

  • total_latency

    The total wait time of timed occurrences of the I/O event.

  • avg_latency

    The average wait time per timed occurrence of the I/O event.

  • max_latency

    The maximum single wait time of timed occurrences of the I/O event.

  • read_latency

    The total wait time of timed read occurrences of the I/O event.

  • write_latency

    The total wait time of timed write occurrences of the I/O event.

  • misc_latency

    The total wait time of timed other occurrences of the I/O event.

  • count_read

    The number of read requests for the I/O event.

  • total_read

    The number of bytes read for the I/O event.

  • avg_read

    The average number of bytes per read for the I/O event.

  • count_write

    The number of write requests for the I/O event.

  • total_written

    The number of bytes written for the I/O event.

  • avg_written

    The average number of bytes per write for the I/O event.