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Prestige Scheduler Version 5 On-Line Documentation (preliminary) |
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Board Resources |
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Adding or Editing Resources |
Board resources are the finite-capacity elements against which processes are scheduled. Each board resource gets its own row on the EPB. All processes that are assigned to the resource are queued against it as process bars. Each process bar is sized proportional to the time that the process has been planned to take. The position that a process bar occupies on the row in relation to other process bars on the same row is dependent on a number of factors, which are covered elsewhere in this documentation. You add resources by selecting Board Resources from the Maintenance Menu. Here is the screen that is used:
To add an assignment group, right-click within the bounds of the Assignment Groups list and choose Add new group from the context menu. The following screen is displayed:
The description is used almost exclusively elsewhere in the system. It is also important that you define all your downtime proformas before starting to add board resources. Then, you can drag and drop the downtime proformas that will apply to each resource you add here. To add a new resource to the end of the current list of resources (if any), you can just press [F4]. You can also add a new resource either before or after a particular resource that has already been defined. To do this, select the appropriate option from the [Add New] drop-down on the tool bar, after you have selected an existing resource in the list. The data for any existing resource can be edited simply by selecting the resource from the resource list on the left. As you select a resource in the list, its details are displayed on the right. Any white text box can have the details changed. You can also change assignment groups and downtime proformas etc. A resource can be a member of more than one assignment group. |
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Infinite/ Queue Rows |
Prestige Scheduler is considered a finite-capacity scheduling system. This means that resources are generally able to do only one process at a time and hence processes must be positioned on the row so that one process ends before the next can begin. We term this the “row constraint”. However, marking a resource row as infinite will defeat this normal criterion. In the case of a row marked as infinite, the scheduler ignores any row constraint for a process scheduled on the row. This means that the process will only be constrained by any predecessors it may have. PS will allow more than one process to occupy the same time space on an infinite row. Infinite rows are good for setting up queues (see Equivalence Groups). Such rows can also be used where one row represents a resource whose capacity can be adjusted to fit the demand. Some finishing resources such as “hand gluing” etc. may fit this model. |
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Multi board support |
As of version 5.0, only one board is available to define resources for. As of v5.1, you will be able to define several boards. Then, each resource will need to be attached to one of the boards you have set up. The rules for creating multiple boards will be detailed in release notes delivered with v5.1. You should be aware though that resources for multiple boards must be sequential in terms of default routing order. In this context we will talk about “up-stream” and “down-stream” boards. |
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Equivalence Groups |
You make two or more resources a member of a common equivalence group when the resources are essentially identical and you want to be able to balance the loadings across the members. PSv5 allows you to do this, but you need to add an additional row that becomes the “queue” row for the equivalence group. When jobs are imported, processes assigned to the group are imported initially onto the queue row (which generally needs to be marked as “infinite”). Context menu options are available for queue rows which allow you to both empty the queue and also to re-balance an equivalence group. To establish an equivalence group, create the resources (including the Q) with the same non-zero equivalence group value. It is also important that the members of an equivalence group have common assignment groups and have the same default routing order. |
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Routing Order |
When Prestige Scheduler schedules a job on the board, it needs to know the order in which processes scheduled against the resources must be done. The routing order determines this rule. Unless a process is governed by an external constraint, it is constrained by its predecessors. A predecessor is defined as a process for the same job and part that has the next lower routing order. Conversely, a successor is defined as a process for the same job and part which has the next higher routing order. If more than one process for the same job and part has the SAME routing order, these processes are said to be “concurrent” and if they are scheduled on different resources, they can run at the same time. Concurrent processes will share common predecessors, if any. When you define a resource, you can nominate a default routing order. The default is used either when you import processes and the routing order is not explicitly supplied; or you add a process from scratch. The routing order for a process, once defined, can be changed at will. |
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Standard Lead |
See Job Browser for a definition of the Standard Lead useage. |
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Speed Factor |
The speed factor provides a simple mechanism to allow for run time differences when a process is re-assigned to another resource within the same assignment group. You choose a resource within a group to have the speed factor of 1.0000. Then you rate each other resource within the group according to this base resource. If a resource runs at around 75% that of the base, its speed factor will be 0.7500 and so on. |
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Minimum Lag |
See Job Browser for an explanation of the Minimum lag value (under Minimum quantity). |
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