You can validate and run mappings on the Spark engine in the Hadoop environment.
The Data Integration Service validates whether the mapping can run in the selected environment. You must validate the mapping for an environment before you run the mapping in that environment.
Spark Engine
When you select the Hadoop environment, the Data Integration Service pushes the mapping to a compute cluster and processes the mapping on a Spark engine. The Data Integration Service generates an execution plan to run mappings on the Spark engine.