The job command makes it possible to execute custom Tcl scripts once or repeatedly.
The Content Management Server and the Template Engine differentiate between system jobs and user jobs. System jobs are predefined routines for the purpose of, for example, transferring update records to the Template Engine in the context of the incremental live server export. They can neither be deleted nor modified. User jobs, on the other hand, can be created, modified, and deleted as desired. Both job categories share the same name space, i. e. two jobs cannot have the same name even if they belong to different categories.
The jobs in a category are placed in the execution queue at execution time unless they have already been added to it. This prevents a more frequently executed job from being placed in the queue several times if this job or another one is currently running.
All jobs in a category are processed sequentially since they share the same execution queue. This has the advantage that several jobs can be triggered at the same time and will nevertheless be processed consecutively (initiation and execution are asynchronous). Jobs in different categories, however, are processed in parallel.
Please note that jobs are only executed if the CMS application concerned (CM or TE) runs in server mode. If the application was started with the -single command line argument and is not running as server at the same time, jobs will be queued but only executed after the server has been started again.
The execution of jobs is logged. The maximum number of log entries the system creates per job is determined by the value of jobMaxLogLength which is part of the tuning system configuration entry.