c D SCHEDULE Automated Job Submission System Guide and Reference Manual D SCHEDULE
Automated Job Submission System
Guide and Reference Manual
Q Chapter 3
Resource Variables and Preprocessing
G This chapter presents detailed descriptions of advanced aspects of job < scheduling using SCHEDULE . These features include:
J - Resource variables: Resource variables are can be H read . A variable can be read by a job to determine a resource action J and can be modified by a job for future interaction. Variables can also B be placed into a job's command list using preprocessor commands.B
- Expanded variables: In addition to simple H resource variables EnterpriseSCHEDULE supports a rich set of H variable expressions that feature simple or complex math expressions, H date expressions and character expressions. This extends the power of J variables and allows for run time calculation of dates and other values.J
- Pre-processor substitution: The commands in a job I are run through a pre-processor searching for control instructions and = variable replacement expressions before the job is created.
S 3.1 Advanced job interaction
E This section explains advanced job interaction and gives examples of @ how to gain even more control of your job runs. While initiates – ( Section 2.1.8) and prerequisites ( Section 2.1.10) allow a full range of H interactivity between jobs, the advanced techniques described below can 8 add an extra degree of programmability to your job runs.
C In a standard job interaction sequence, when all prerequisites are B completed the job is run and then the initiate list is processed, H executing connected jobs. However, suppose you want to suppress the job H if another job is currently running? Maybe you want to limit the number H of jobs that can access a resource like a database at the same time. Or C maybe you want to be able to set a variable that shuts off a whole D section of your job group or even the whole group when you see fit. > This is where advanced job programming comes into the picture.
E Unlike initiates and prerequisites, a job's general resource list is F not connected to other jobs. Instead, the commands in a resource list ? perform variable evaluation dictating the behavior of the job. H Depending on the results of the variable evaluation, the job run can be E suppressed, put in a wait state, or a new value can be assigned to a variable.
F In addition to the resource list, the initiate list, the prerequisite @ list and the end actions list can also be used for advanced job @ interaction, though in different ways. Each of these methods is explained later in this section. ; 3.1.1 How jobs are processed
B In order to understand advanced job interaction, you should first E understand how jobs are processed and what techniques can be used to H add to that process. This list illustrates the order that job lists are H processed and the type of advanced job processing that can be performed using these lists.
I - Job is initiated - A job can be initiated either B by a start time, a submit command or another jobs initiate list) F
- Prerequisites - The first step of a job is the G processing of the prerequisites list. The prerequisite job checks to > see if the prerequisites have successfully executed. If all > prerequisites have been executed, the next step occurs. The F prerequisite list can include IF statements that include or exclude particular jobs. H
- Resources - The resource list is where the bulk B of advanced job programming occurs. Here IF-THEN statements are H processed that can check or alter the value of a variable, suppress a E job run or cause a wait to occur. These techniques will prove very useful. E
- Job is run - The job is submitted into batch , using the attributes assigned for the job. G
- End Action - The end action list contains post G job processing that occurs whether or not the job is successful. The G end action list can include IF-THEN statements that checks or alters the value of a variable. I
- Initiates - The initiates list contains the jobs G that will be executed upon successful completion of the current job. A The initiate list can include IF statements include or exclude I particular jobs. Other conditions can also be used to control the next job step.