30.4.3.49 The wait_classes_global_by_latency and x$wait_classes_global_by_latency Views

These views summarize wait class total latencies, grouped by event class. By default, rows are sorted by descending total latency. Idle events are ignored.

An event class is determined by stripping from the event name everything after the first three components. For example, the class for wait/io/file/sql/slow_log is wait/io/file.

The wait_classes_global_by_latency and x$wait_classes_global_by_latency views have these columns:

• event_class

  The event class.

• total

  The total number of occurrences of events in the class.

• total_latency

  The total wait time of timed occurrences of events in the class.

• min_latency

  The minimum single wait time of timed occurrences of events in the class.

• avg_latency

  The average wait time per timed occurrence of events in the class.

• max_latency

  The maximum single wait time of timed occurrences of events in the class.