How the Solver Works
Navigator's solvers operate under the following principles:
The solver will look for rates from every facility of the "Service Role" type to each customer for each customer's product at that product's shipment size for the designated "Service Mode".
If "Service Mode" is "Current" (as in the image below), then a customer's current service mode options will be considered.
If the solver finds the existing rate in the model, i.e., the relevant activity on an existing lane, then the solver will use that rate.
If the solver does not find a rate it's looking for, it will look up the rate from the reference database based on the origin and destination and the product's particular transportation characteristics.
Effectively, the number of flow variables (ignoring higher tier, non-service lane related flow variables) as:
#Service Facilities * #Demands (-># rows in Demands sheet)
Time-Intensive Parts of the Process
There are two time-intensives parts of the process:
Getting necessary reference data
If "Service Mode" is "Current" (as in the image below), then a customer's current service mode options will be considered.
The solver must first determine the rates it needs - what the potential flows in the models are - and then connects to the reference database in order to get those rates.
The speed at which reference data can be pulled is dependent on a number of factors, but you can generally expect 250k values to be pulled within 30s.
Running the solve algorithm
After the solver determines the potential variables, the algorithm will run until either the optimal solution is found or until a certain optimization threshold is met for particularly complex models.
Note: Adding capacity or BOM constraints to the model will result in a model that is potentially much more complex and therefore will take longer to solve than a model without those constraints.