You do not need to make any changes to the spark-defaults.sh file! This section is just FYI.
Spark properties set in the spark-defaults.sh file control most Spark parameters.
The spark-defaults.sh file is located in the following directory: USB:\spark\conf\
Note, the actual file in the directory will be named spark-defaults.conf.template. In order to set configurations in this file, first copy the file to a new file named spark-defaults.sh and make the changes in the new file.
Example file:
spark.master spark://5.6.7.8:7077
spark.executor.memory 512m
spark.eventLog.enabled true
spark.serializer org.apache.spark.serializer.KryoSerializer
spark.driver.memory 5g
spark.executor.extraJavaOptions -XX:+PrintGCDetails -Dkey=value -Dnumbers="one two three"
Instead of setting Spark properties in this file, it is possible to also set properties during run time in the SparkConf or via the spark-submit command. For details, see: https://spark.apache.org/docs/latest/configuration.html
Properties set directly on the SparkConf take highest precedence, then flags passed to spark-submit or spark-shell, then options in the spark-defaults.conf file.