Scheduling tasks
The Activities, Communities, Files, Forums, News, Search, and Wikis applications use the IBM® WebSphere® Application Server scheduling service for performing regular tasks. You can use wsadmin commands to change the schedule by which a task runs or to disable a scheduled task altogether.
The scheduling service allows you to reliably process workloads using parallel processing, and to schedule resource-intensive tasks during off-peak hours when there is low traffic. For more information about the WebSphere® Application Server scheduling service, see Developing and scheduling tasks in the WebSphere® Application Server documentation.
second minute hourOfDay dayOfMonth month dayOfWeek
Some
tips when specifying the cron schedule values: - Specify an asterisk (*) to indicate that you want to select all options. For example, if you specify * as the value of the dayOfWeek parameter, the task runs every day of the week.
- Always set seconds to 0, except for in the Profiles task, which
runs every 20 seconds and is specified using the syntax */20.
The */n syntax means take the first value in the range, and then every nth value. So, if you specified */3 in the month position, the task would run quarterly in January, April, July, and October.
- dayOfMonth and dayOfWeek are mutually exclusive; always set one
to ?.
The ? indicates that no value is being provided.
- You can indicate in a single cron expression that you want a task
to run multiple times by using multiple values separated by commas
or you can specify a range by separating the values with a dash.
- You can specify the value in dayOfWeek using SUN, MON or using numbers 1,2 where 1 represents Sunday.
- You can specify JAN, FEB for the value of month or by using numbers 1,2 where 1 represents January.
- To specify one or more seconds, use the values 0, 1, ... 59.
- To specify one or more hours, use the values 0, 1, ... 23.
- If it is easier for you to read and define the schedule by separating
out the values into multiple cron expressions, you can do so and use
a | to concatenate the values into a composite schedule. For example,
you could indicate that you want to schedule to run quarterly at 3:45
PM on the second day of the month using the following string:
0 45 15 2 1 ? | 0 45 15 2 4 ? | 0 45 15 2 7 ? | 0 45 15 2 10 ?
To see examples of cron expressions and what they mean, see Examples of scheduler values. For more information on the Cron calendar, see UserCalendar interface in the WebSphere® Application server product documentation.
To disable a scheduled task, use wsadmin commands.