Schedulers collection
Use this page to manage scheduler configurations. Schedulers are persistent and transactional timer services that can run business logic. Each scheduler runs tasks independently and has a programming interface accessible from JEE applications using the JNDI. We can also manage schedulers using a JMX (JMX) MBean. See the scheduler documentation in the Information Center for details on how to configure and use schedulers.
To view this administrative console page, click Resources > Schedulers.
Name
Name of the data source where persistent tasks are stored.
| Information | Value |
|---|---|
| Data type | String |
JNDI name
Specifies the JNDI name of the work manager, which is used to manage the number of tasks that can run concurrently with the scheduler. The work manager also can limit the amount of Java EE context applied to the task.
The JNDI name specifies where this scheduler instance is bound in the name space. Clients can look this name up directly, although the use of resource references is recommended.
| Information | Value |
|---|---|
| Data type | String |
Scope
Scope of the configured resource. This value indicates the location for the configuration file.
Data source JNDI name
Alias for the user name and password used to access the data source.
Any data source available in the name space can be used with a scheduler. Multiple schedulers can share a single data source while using different tables by specifying a table prefix.
| Information | Value |
|---|---|
| Data type | String |
Table prefix
String prefix to affix to the scheduler tables.
Multiple independent schedulers can share the same database if each instance specifies a different prefix string.
| Information | Value |
|---|---|
| Data type | String |
Poll interval
Interval, in seconds, that a scheduler polls the database. The default is appropriate for most applications.
Each poll operation can be consuming. If the interval is extremely small and there are many scheduled tasks, polling can consume a large portion of system resources.
| Information | Value |
|---|---|
| Data type | Integer |
| Units | Seconds |
| Default | 30 |
| Range | Any positive long integer |
Work manager JNDI name
Specifies the JNDI name of the work manager, which is used to manage the number of tasks that can run concurrently with the scheduler. The work manager also can limit the amount of Java EE context applied to the task.
The work manager is a server object that serves as a logical thread pool for the scheduler. Each repeating task created using this scheduler uses the Number of alarm threads specified in the work manager, which affects the number of tasks that can run concurrently. Use the work manager Service Names property to limit the amount of context information that is propagated to the task when it runs.
When a task runs, the task is run in the work manager associated with the scheduler instance. We can control the number of actively running tasks at a given time by configuring schedulers with a specific work manager. The number of tasks that can run concurrently is governed by the Number of alarm threads parameter on the work manager.
Verify tables
Specifies to validate that scheduler data sources, table prefixes, security authentication information and tables are configured correctly.
Use this verification method in production and development environments without altering database properties.
Create tables
Specifies to create the necessary tables and indices required for a scheduler to operate.
This method of creating scheduler tables is designed for simple topologies and development environments. Use the supplied scheduler data definition language files for advanced or production environments and for databases that do not support this feature.
Drop tables
Removal of tables and indices required for schedulers to operate.
This method of removing scheduler tables and indices is recommended for development environments and does not delete previously scheduled tasks.
Related concepts
Related tasks
Reference topic