I'd like to understand how the Solve tool works when it's looking for an itinerary on a NA Route layer where each segment has a cost. What is the algorithm that Solve uses? I'd like to optimize my model: the idea I have is to create a buffer around the stop locations in order to limit the number of route segments around the stops. Then, execute the Solve tool on that buffer area. Would it make the solve operation quicker? Is there any difference (in terms of processing time) between a Solve performed on a small network and a Solve performed on a bigger one?
In general, it takes the same time to solve the same route on a small or large network. The problem may happen if there is no path between the two stops. In that case the entire network is being searched before realizing there is no path and that can take longer on a larger network.
If you are running into some performance issues then you can explain a bit more what you need to achieve and we can analyze it more.