Period

Periods are either cyclic, such as a week or 28-day period, or noncyclic, such as an academic semester.

Cyclic periods

Defined by their origin date and their length: a cyclic period starts on a specific date and has a specified number of days. There are two kinds of cyclic periods:

work-days-only cyclic periods: Only working days are considered.
all-days cyclic periods: All the days are considered.

Noncyclic periods

Defined by the origin date of each interval and can optionally have an end date for each interval.

Periods can be combined with offsets to create run cycles and define when a job stream runs. For example, an offset of 1 in a weekly period specifies Monday. An offset of 10 in a monthly period specifies the tenth day of each month.

The long-term planning process uses the calendar information, the period definitions, and the run cycle, to determine the days on which an application is scheduled to run.

If you run workload on fixed days of the week, month, or year, and take one of the standard HCL Workload Automation for z/OS actions when this day falls on a non-working day, you do not need to create your own periods. You can describe most cases with rules such as:

First Sunday in June
First working day in the week
Last Friday in the year
Last non-working day in the month

If you use rules with their built-in calendar cycles (days of the week, months of the year, and so on), you probably need to create only special noncyclic periods, such as university semesters and tax years. The following sections show some examples of types of periods.

Cyclic period examples

Examples of cyclic periods are a day, a week, and a fortnight, with fixed intervals of 1 day, 7 days, and 14 days, respectively. An academic semester cannot be described as a cyclic period, because spring, summer, and fall semesters have different lengths. The following example shows a lunar calendar month, assumed to be 28 days:

Period name: Moon
Type: Cyclic based on all days
Interval: 28 days
Interval origin: 7 February 2009 (date of a new moon)

Non-cyclic period examples

Examples of non-cyclic periods are a quarter and a payroll period. You specify the start of each interval of a non-cyclic period with an origin date. This example shows a period for university semesters, with the interval origin and end specified for each semester:

Period name: Semester
Type: Non-cyclic
Interval origin: 26 August 2009, 13 January 2010, 9 June 2010.
Interval end: 13 December 2009, 16 May 2010, 28 June 2010

Non-cyclic periods have a once-a-year maintenance overhead when you must create the intervals for the coming months. For this reason, carefully consider how flexible your period definitions are, and remove potentially duplicated definitions.