{"data":{"markdownRemark":{"html":"

You can start using the Simudyne SDK without defining any configuration, since sensible default values are provided. Later on you might need to amend the settings to change the default behavior. Typical examples of settings that you might amend:

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Where configuration is read from

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The Simudyne SDK reads the config from a simudyneSDK.properties file in the root directory of a project. If this file cannot be found, default values are set for all config.

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All config properties can also be overwritten dynamically in the model code. Use getConfig() to get the config for a specific model, and setString(), setBoolean(), setLong() or setInt() to set config of a specific type.

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ModelConfig.java

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public class Housing implements Model {\n\t@Constant public boolean distributed = false;\n\n  public void setup(){\n    if (distributed) {\n    \tgetConfig().setString(\n        \"core-abm.backend-implementation\",\n        \"simudyne.core.graph.spark.SparkGraphBackend\");\n    }  \n  }  \n}
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Best practice

\n Put all config in the properties file, and only override config in the code for values that change based on user input. (An example of this might be overriding if the model should run distributed based on a toggle input). This is so that the model can be compiled and the config changed without having to recompile.\n
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Custom simudyneSDK.properties

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A custom simudyneSDK.properties might look like this

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simudyneSDK.properties

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### SimudyneSDK Configuration file\n\n### NEXUS-SERVER ###\n\nnexus-server.port = 8080\nnexus-server.hostname = 127.0.0.1\n\n### CORE ###\n\n# core.prng-seed = 1640702558671097951\n\n### CORE-ABM ###\ncore-abm.max-messaging-phases = 50\n\n# For serialization-level, choose between : {NONE,CHECKED}\ncore-abm.serialization-level=NONE\ncore-abm.serialize.agents=true\ncore-abm.serialize.links=true\ncore-abm.serialize.accumulators=true\ncore-abm.local-parallelism=8
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\nThe above hostname will make sure that the server and console are ONLY available locally. If you wish to deploy to a server you should change the hostname either to the IP address, or more commonly 0.0.0.0\n
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Configuring Distributed ABMs (with Spark)

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If the model is to be run as a distributed model using Spark, the core-abm.backend-implementation needs to be set in the config, and the following Spark settings.

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simudyneSDK.properties

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core-abm.backend-implementation=simudyne.core.graph.spark.SparkGraphBackend\n\n# Default Spark settings. Comment these lines if you will be providing the configuration\n# via spark-submit or similar, otherwise these settings are required.\n\n# For log-level, choose between : {OFF, FATAL, ERROR, WARN, INFO, DEBUG, TRACE, ALL}\n\ncore-abm-spark.master-url = local[*]\ncore-abm-spark.spark.executor.memory = 2g\ncore-abm-spark.spark.sql.shuffle.partitions = 24\ncore-abm-spark.checkpoint-directory = /var/tmp\ncore-abm-spark.log-level = WARN
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Configuring Distributed Multiruns (with Spark)

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If the model is to be run as a distributed model using Spark when running as multirun, the core-runner.runner-backend needs to be set in the config, and the following Spark settings.

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core-runner.runner-backend = simudyne.core.runner.spark.SparkRunnerBackend\n\n# Default Spark settings. Comment these lines if you will be providing the configuration\n# via spark-submit or similar, otherwise these settings are required.\n\n# For log-level, choose between : {OFF, FATAL, ERROR, WARN, INFO, DEBUG, TRACE, ALL}\n\ncore-runner-spark.master-url = local[*]\ncore-runner-spark.spark.executor.memory = 2g\ncore-runner-spark.spark.sql.shuffle.partitions = 24\ncore-runner-spark.log-level = WARN\ncore-runner-spark.task.cpus = 1
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