Optimize Options

Key Concepts

This dialog is used to initiate a process of automatically reconstructing all (or part) of the schedule to improve its quality and incorporate all recent data updates into the schedule. The schedule optimization is performed based on the Optimize Settings configured from the drop-down menu of the Optimize tab.

There are two types of Optimize Settings to choose from:

  • Shared Scenario Settings: These settings are stored for each Scenario. Using the Scenario Settings is usually the better option (rather than the "Personalized Optimize Settings" option) daily when multiple planners use the system. If each planner uses the Scenario Optimized Settings, then you can be sure that everyone is optimizing in the same way. To use this, you must go to User Settings | Preferences | Optimize and check the 'Use shared optimize settings' option. Note: the Scenario Optimize Settings are also used by the Scheduling Agent when automated Optimizations are performed.
  • Personalized Optimized Settings:  These settings are stored separately for each User to retain each User's preferences.  These can be useful in performing What-If analyses or for general experimentation.

Setting Up the Optimize Settings

  • Optimize Activities Starting At: This specifies the starting point for the optimization, and only activities that start after this specified time are included in the rescheduling. This feature is useful if the schedule must remain stable in the short term for shop floor logistics or other reasons. The following options are available:
    • Beginning of the Schedule: This will look at all of the jobs from the beginning of the schedule to optimize and reschedule. 
    • End of the Frozen Span: This will only look at jobs scheduled after the Frozen Span set during optimization. This is helpful when you want to prevent rescheduling jobs at the beginning of the schedule.
    • End of the Stable Plan Span: This will only look at jobs scheduled after the Plant Stable Span set during optimization. This is helpful when you want to prevent rescheduling jobs at the beginning of the schedule.
    • Specific Date/Time: When this option is selected, an additional field appears underneath where the user can set a specific date and time to start the optimization process.
  • Jobs to Exclude: Any Jobs that match the checked options in the Jobs to Exclude section will not be scheduled during the Optimize. If they were previously scheduled, then they will be unscheduled during the Optimize. This section gives planners control when choosing which Jobs enter the schedule. For example, a planner might want to only include Firm Jobs in the schedule as these are sure to be executed. However, a planner may also wish to see how the workload will be affected if Estimates, CTP, or Planned Jobs are included. Note: Individual Jobs can also be Excluded from the schedule by checking the Do Not Schedule option. Excluded Jobs are shown in the Excluded tab of the Jobs pane. The Exclude options are:
    • Planned: The Job’s commitment is planned. A planned job is usually a computer-generated order that a planner has not yet firm. The most common example would be an MRP-generated job that was created as a suggestion to satisfy material requirements for a higher-level job. 
    • New: The Job was newly created and never scheduled.
    • Estimates: The Job’s commitment is an estimate. (This includes Capable To Promise Jobs). Estimates are usually quote used for generating an expected ship time. 
    • Unscheduled: The Job was previously unscheduled by a planner.
    • On-Hold: The Job’s On-Hold status is set to On-Hold. (A status of “Some Operations On-Hold” does not qualify). Note: if on-hold jobs are scheduled, they will start after the Hold-Until Date of each operation.
  • Optimize Rule(s) to Use: This field specifies which sequencing rules to use during the optimization.
    • Use one Rule for all Resources: The optimize rule specified here will be used on all the resources during the optimization. This option can be used to easily experiment with different optimized rules without editing each resource`s rule.
    • Use Normal Resource Rules: Use each resource’s “Normal Rule” during the optimization. Normal Rules represent the normal set of optimizing rules used for the resource's normal operation.
    • Use Experimental Resource Rules: Use each resource’s “Experimental Rule” during the optimization. Experimental rules are the set of optimized rules generally used in What-If scenarios as they provide a way to edit individual resource rules without losing the Normal Rule settings.

Note: The Normal and Experimental Rules can be modified by double-clicking on a resource on the left of the Gantt and accessing the Optimization | Optimize Rules tab.

  • Release Rule(s) to Use: Each manufacturing order is prevented from scheduling until it is released. Release Rules determine how manufacturing orders are released for scheduling during optimization and therefore supersede the optimize rules.
    • JIT with Resource HeadStart: Release dates for each operation are calculated to target a “Just in Time” completion of the Job/MO need a date. The JIT Slack Days can be specified for each resource by double-clicking on the resource and changing the “Headstart Span” field of the Optimize tab. Each manufacturing order will be released based on the lead Activity’s JIT Start Date minus the HeadStart Span specified for each resource.
    • JIT with Global HeadStart: This option will enable a text box next to the drop-down menu where users can set the number of JIT Slack days to be applied to all resources. Each manufacturing order will be released based on the lead Activity’s JIT Start Date minus the JIT Slack specified.
    • Drum-Buffer-Rope: The DBR calculations are used to manage the release date for operations that have consistent capacity-constrained resources. Each manufacturing order is released based on its DBR Release Date minus the JIT Slack Days specified in the optimize settings.
  • Account for Offline Intervals: This option modifies the way Head Start is calculated, depending on whether offline intervals should be accounted for or not. This is useful for users with a short head start as activities released on offline capacity intervals (e.g., weekends) are pushed to the next available interval (e.g., Monday), which causes unused capacity at the end of the week and bottlenecks on Monday. ***Note: This is available in versions 11.48 and later. Click here for more information about this feature.

Note: The greater the JIT Slack Days value, the earlier the manufacturing order can start.

  • Auto-Join Manufacturing Orders: If this is checked, then manufacturing orders with the same AutoJoinGroup scheduled consecutively in one capacity interval are joined during the optimization. This can be helpful in situations were releasing a single MO to the shop floor in a shift is preferred.

See also: MPS/MRP Process.