contains current stage events. The table stores one row per
thread showing the current status of the thread's most recent
monitored stage event, so there is no system variable for
configuring the table size.
Of the tables that contain stage event rows,
events_stages_current is the most
fundamental. Other tables that contain stage event rows are
logically derived from the current events. For example, the
are collections of the most recent stage events that have
ended, up to a maximum number of rows per thread and globally
across all threads, respectively.
For more information about the relationship between the three stage event tables, see Performance Schema Tables for Current and Historical Events.
For information about configuring whether to collect stage events, see Section 10.5, “Performance Schema Stage Event Tables”.
has these columns:
The thread associated with the event and the thread current event number when the event starts. The
EVENT_IDvalues taken together uniquely identify the row. No two rows have the same pair of values.
This column is set to
NULLwhen the event starts and updated to the thread current event number when the event ends.
The name of the instrument that produced the event. This is a
NAMEvalue from the
setup_instrumentstable. Instrument names may have multiple parts and form a hierarchy, as discussed in Chapter 7, Performance Schema Instrument Naming Conventions.
The name of the source file containing the instrumented code that produced the event and the line number in the file at which the instrumentation occurs. This enables you to check the source to determine exactly what code is involved.
Timing information for the event. The unit for these values is picoseconds (trillionths of a second). The
TIMER_ENDvalues indicate when event timing started and ended.
TIMER_WAITis the event elapsed time (duration).
If an event has not finished,
TIMER_ENDis the current timer value and
TIMER_WAITis the time elapsed so far (
If an event is produced from an instrument that has
TIMED = NO, timing information is not collected, and
For discussion of picoseconds as the unit for event times and factors that affect time values, see Section 5.1, “Performance Schema Event Timing”.
These columns provide stage progress information, for instruments that have been implemented to produce such information.
WORK_COMPLETEDindicates how many work units have been completed for the stage, and
WORK_ESTIMATEDindicates how many work units are expected for the stage. For more information, see Stage Event Progress Information.
EVENT_IDvalue of the event within which this event is nested. The nesting event for a stage event is usually a statement event.
The nesting event type. The value is