DataYatriSpark, seen under the hood
Simulate

Simulation/Spark

Educational simulation
Spark

Tungsten

Binary rows and whole-stage codegen — until a Python UDF.

Watch the canvas:Tungsten / codegenPython UDF fallbackLive simulation
Unsafe / binary rowoff-heap bytesWholeStageCodegenfused loopPythonUDFobjects againNot Java objects on the hot path.
Tungsten = binary rows + codegen. UDFs throw you back to the slow path.