Auto Scheduler FAQs
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What if I want to find a feasible schedule and I’m not concerned about the objective value?
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The scheduler cannot find a feasible schedule. What should I do?
What licenses do I need to run Auto Scheduler?
This depends on how you wish to process your data.
If you are planning on optimizing schedules using Datamine's Summit Scheduler cloud solution, you will need the following licenses:
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Studio OP application license.
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Summit Scheduler
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Auto Scheduler
If you wish to run advanced local optimizations, you will need:
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Studio OP application license.
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Auto Scheduler
If you wish to run only basic optimizations locally, you will only need a Studio OP application license.
What if I want to find a feasible schedule and I’m not concerned about the objective value?
Set the Gap to a very large value, say 1000, and the optimizer will stop as soon as it has found a feasible schedule.
The scheduler cannot find a feasible schedule. What should I do?
Try first solving for the first period only to check that there is at a solution for this period, and then incrementally increase the number of periods. Common causes of infeasibility that you should check are as follows:
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Minimum bounds on targets are a common cause of infeasibility, so consider relaxing or removing these. Note that, with an appropriate objective in place, often minimum bounds are satisfied by an optimal schedule without needing to specify them. For example, setting a minimum bound on the tonnes sent to a plant is often unnecessary with an objective to maximise cash flow.
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No valid destination for a block. Check that there are valid destination for all blocks being scheduled.
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Incorrect loader capacities or destination capacities. Check that loaders and destinations have a valid capacity and not a zero capacity for example.
Note that there is not always a simple explanation for why there is no valid schedule. It could be due to the complex interaction of a number of different constraints that leads to infeasibility and there is no single constraint that is the problem. Ultimately, it may come down to a matter of trial and error to isolate the problem by removing constraints until a schedule is found and then reapplying them incrementally to identify the issue.
The scheduler is running for a long time and has not been able to find an optimal schedule. What should I do?
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Try first solving for the first period only to find a solution for that period, and then incrementally increase the number of periods.
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Consider also providing the Scheduler with a pre-schedule to partially fix the schedule, which will generally reduce the time for the schedule to finish.
These two approaches may be applied together by iteratively scheduling a reduced number of periods and iteratively fixing each period one at a time from first to last.