MySQL 9.0 Reference Manual Including MySQL NDB Cluster 9.0
The component_scheduler_tasks table
contains a row for each scheduled task. Each row contains
information about the ongoing progress of a task that
applications, components, and plugins can implement,
optionally, using the scheduler component
(see Section 7.5.5, “Scheduler Component”). For example, the
audit_log server plugin utilizes the
scheduler component to run a regular,
recurring flush of its memory cache:
mysql> select * from performance_schema.component_scheduler_tasks\G
*************************** 1. row ***************************
NAME: plugin_audit_log_flush_scheduler
STATUS: WAITING
COMMENT: Registered by the audit log plugin. Does a periodic refresh of the audit log
in-memory rules cache by calling audit_log_flush
INTERVAL_SECONDS: 100
TIMES_RUN: 5
TIMES_FAILED: 0
1 row in set (0.02 sec)
The component_scheduler_tasks table has the
following columns:
NAME
The name supplied during the registration.
STATUS
The values are:
RUNNING if the task is active and
being executed.
WAITING if the task is idle and
waiting for the background thread to pick it up or
waiting for the next time it needs to be run to
arrive.
COMMENT
A compile-time comment provided by an application,
component, or plugin. In the previous example, MySQL Enterprise Audit
provides the comment using a server plugin named
audit_log.
INTERVAL_SECONDS
The time in seconds to run a task, which an application,
component, or plugin provides. MySQL Enterprise Audit enables you to
specify this value using the
audit_log_flush_interval_seconds
system variable.
TIMES_RUN
A counter that increments by one every time the task runs successfully. It wraps around.
TIMES_FAILED
A counter that increments by one every time the execution of the task fails. It wraps around.