topic Re: How to make AStar cache paths? in FlexSim Forum

How to make AStar cache paths?

lars_jacobsen_ScandiSim — Thu, 07 Jul 2022 07:56:14 GMT

[ FlexSim 22.1.2 ]

When I run a model using Astar, the Paths Cached are zero. Are there any particular requirements to make AStar cache paths?

The issue is that according to the performance profiler AStar search new paths uses approx. 99.99% of the model computing time.

Re: How to make AStar cache paths?

moehlmann_fe — Thu, 07 Jul 2022 08:36:43 GMT

Just in case: Have you clicked on Apply and/or OK after checking that option?

Does it work in other models (such as the one below)?

PathCachingTest.fsm

Re: How to make AStar cache paths?

lars_jacobsen_ScandiSim — Thu, 07 Jul 2022 08:57:12 GMT

I have clicked Apply after checking the option. Caching works fine in your model, but not in my model. Unfortunately I cannot share my model as it is confidential. Thus I was hoping that someone knows if there is any special requirements which needs to be meet for the caching to work.

Re: How to make AStar cache paths?

moehlmann_fe — Thu, 07 Jul 2022 09:06:19 GMT

Not that I know.

Any idea what might be the issue here @anthony.johnson?

Re: How to make AStar cache paths?

ralf_gruber — Thu, 07 Jul 2022 11:42:01 GMT

Lars,

The GUI shows zero Paths Cashed, but also zero Paths Requests...are you sure the TEs using A-Star have done any transports? Or was the screenshot taken after reset?

Re: How to make AStar cache paths?

anthony_johnsonT83CM — Thu, 07 Jul 2022 20:47:13 GMT

Are you using dynamic barriers? A* cannot cache paths if you have any code that adds dynamic barriers. The path caching mechanism must be able to create a tuple key that is based on the set of active conditional rules. It cannot create such a key if there are dynamic barriers, so it must recalculate every single time. If the set of possible dynamic barriers is sufficiently small, you should use conditional rules instead of dynamic barriers. If the number of possible dynamic barriers is too large to use conditional rules, then path caching would be useless anyway because it would almost never be able to reuse the same cached path because every possible configuration of dynamic barriers would require its own key, and that could overload your memory.

Re: How to make AStar cache paths?

Jeanette_Fullmer — Tue, 12 Jul 2022 19:44:48 GMT

Hi @Lars Christian J2, was one of anthony.johnson's or Lars Christian J2's answers helpful? If so, please click the "Accept" button at the bottom of the one that best answers your question. Or if you still have questions, add a comment and we'll continue the conversation.

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