How to run Jsprit on multiple threads?

[tortabevonas]

I'm trying to run Jsprit on a 8-core processor, so I think it would benefit from running in multiple threads.

This's how I tried it:

VehicleRoutingAlgorithmBuilder vraBuilder = new VehicleRoutingAlgorithmBuilder(problem, "ac.xml");
vraBuilder.addCoreConstraints();
vraBuilder.setNuOfThreads(8);
vraBuilder.addDefaultCostCalculators();

VehicleRoutingAlgorithm algorithm = vraBuilder.build();

But it still doesn't cause 100% processor load. What am I doing wrong?

Thank you for your help!

Aron

[tortabevonas]

Update: I can see this line in console after starting Jsprit:

jsprit.core.algorithm.io.VehicleRoutingAlgorithms - setup executor-service with 8 threads

But it still runs as slow as on a single thread. How should I achieve full processor usage?

[jsprit]

95 percent of the computation time is spent on re-inserting jobs, i.e. finding the best insertion position. Basically, jsprit goes through every route to find the best insertion position of a job. With the concurrency mode you can only distribute the task to find the best position in an entire routes (you cannot split a route into subroutes). Thus, if you only have one route, only one thread is used no matter how many you configured. If you have 20 routes and configured 4 threads, you can distribute 5 to each thread. Note, that when you use BestInsertion, your problem must be relatively large to gain from concurrent calc (otherwise performance gets worse due to the overhead of distributing). If you use RegretInsertion, I think that you can always gain. But you need to analyse it.



The associated calculations can be done concurrently. However

Am 17.12.14 12:44, schrieb tortabevonas:

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[tortabevonas]

Thank you for the informations!

I've tried to use "regretInsertion", but it says that

java.lang.IllegalStateException: currently only 'bestInsertion' is supported

[jsprit]

Do you use v1.5?

Am 17.12.14 13:20, schrieb tortabevonas:

Thank you for the informations!

I've tried to use "regretInsertion", but it says that

java.lang.IllegalStateException: currently only 'bestInsertion' is supported

[jsprit]

Here is an example: https://github.com/jsprit/jsprit/blob/master/jsprit-examples/src/main/java/jsprit/examples/SolomonWithRegretInsertionExample.java

Look for the algorithm file in the input directory to see how it is configured.

It works with v1.5 only.

Am 17.12.14 13:20, schrieb tortabevonas:

Thank you for the informations!

I've tried to use "regretInsertion", but it says that

java.lang.IllegalStateException: currently only 'bestInsertion' is supported

[tortabevonas]

Thank you!

I was using 1.4.1, this's why it didn't work. Now it spins up all the CPU cores. I'll measure if it runs faster.

[tortabevonas]

I found that it didn't run faster when I ran it with regretInsertion

[jsprit]

How many routes do you have in your solution?

Am 17.12.2014 um 13:36 schrieb tortabevonas <tortab...@gmail.com>:

I found that it didn't run faster when I ran it with regretInsertion

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[tortabevonas]

I had a single route, maybe this's the reason.

In this test I was testing whether it creates a single route for all the deliveries/pickups if the vehicle's capacity makes it possible.