Cloudera Docs

Running Applications with CDS (Cloudera Distribution of Spark)

With CDS 3.5 Powered by Apache Spark (CDS 3.5) and CDS 3.3 Powered by Apache Spark (CDS 3.3), you can run Apache Spark 3 applications locally or distributed across a cluster, either by using an interactive shell or by submitting an application. Running Spark applications interactively is commonly performed during the data-exploration phase and for ad hoc analysis.

The Spark 3 job commands

With Spark 3, you use slightly different command names than with Spark 2, so that you can run both versions of Spark side-by-side without conflicts:

  • spark3-submit instead of spark-submit.

  • spark3-shell instead of spark-shell.

  • pyspark3 instead of pyspark.

For development and test purposes, you can also configure each host so that invoking the Spark 2 command name runs the corresponding Spark 3 executable.

Canary test for pyspark3 command

The following example shows a simple pyspark3 session that refers to the SparkContext, calls the collect() function which runs a Spark 3 job, and writes data to HDFS. This sequence of operations helps to check if there are obvious configuration issues that prevent Spark 3 jobs from working at all. For the HDFS path for the output directory, substitute a path that exists on your own system. 

$ hdfs dfs -mkdir /user/jdoe/spark
$ pyspark3
...
SparkSession available as 'spark'.
>>> strings = ["one","two","three"]
>>> s2 = sc.parallelize(strings)
>>> s3 = s2.map(lambda word: word.upper())
>>> s3.collect()
['ONE', 'TWO', 'THREE']
>>> s3.saveAsTextFile('hdfs:///user/jdoe/spark/canary_test')
>>> quit()
$ hdfs dfs -ls /user/jdoe/spark
Found 1 items
drwxr-xr-x   - jdoe spark-users  0 2016-08-26 14:41 /user/jdoe/spark/canary_test
$ hdfs dfs -ls /user/jdoe/spark/canary_test
Found 3 items
-rw-r--r--   3 jdoe spark-users  0 2016-08-26 14:41 /user/jdoe/spark/canary_test/_SUCCESS
-rw-r--r--   3 jdoe spark-users  4 2016-08-26 14:41 /user/jdoe/spark/canary_test/part-00000
-rw-r--r--   3 jdoe spark-users 10 2016-08-26 14:41 /user/jdoe/spark/canary_test/part-00001
$ hdfs dfs -cat /user/jdoe/spark/canary_test/part-00000
ONE
$ hdfs dfs -cat /user/jdoe/spark/canary_test/part-00001
TWO
THREE

Fetching Spark 3 Maven Dependencies

The Maven coordinates are a combination of groupId, artifactId and version. The groupId and artifactId are the same as for the upstream Apache Spark project. For example, for spark-core, groupId is org.apache.spark, and artifactId is spark-core_2.12, both the same as the upstream project. The version is different for the Cloudera packaging: see Using the CDS 3 Powered by Apache Spark Maven Repository for the exact name depending on which release you are using.

Accessing the Spark 3 History Server

The Spark 3 history server is available on port 18089, rather than port 18088 as with the Spark 2 history server.