spark 2.1.0 session config settings (pyspark)

You aren't actually overwriting anything with this code. Just so you can see for yourself try the following.

As soon as you start pyspark shell type:

sc.getConf().getAll()

This will show you all of the current config settings. Then try your code and do it again. Nothing changes.

What you should do instead is create a new configuration and use that to create a SparkContext. Do it like this:

conf = pyspark.SparkConf().setAll([('spark.executor.memory', '8g'), ('spark.executor.cores', '3'), ('spark.cores.max', '3'), ('spark.driver.memory','8g')])
sc.stop()
sc = pyspark.SparkContext(conf=conf)

Then you can check yourself just like above with:

sc.getConf().getAll()

This should reflect the configuration you wanted.

Setting 'spark.driver.host' to 'localhost' in the config works for me

spark = SparkSession \
    .builder \
    .appName("MyApp") \
    .config("spark.driver.host", "localhost") \
    .getOrCreate()

update configuration in Spark 2.3.1

To change the default spark configurations you can follow these steps:

Import the required classes

from pyspark.conf import SparkConf
from pyspark.sql import SparkSession

Get the default configurations

spark.sparkContext._conf.getAll()

Update the default configurations

conf = spark.sparkContext._conf.setAll([('spark.executor.memory', '4g'), ('spark.app.name', 'Spark Updated Conf'), ('spark.executor.cores', '4'), ('spark.cores.max', '4'), ('spark.driver.memory','4g')])

Stop the current Spark Session

spark.sparkContext.stop()

Create a Spark Session

spark = SparkSession.builder.config(conf=conf).getOrCreate()