title: Spark on EMR : Time for running data in EMR didn't reduce when no of nodes increases
body: <p>My Spark program take a large amount of zip files that contain JSON data from S3. It performs some cleaning on the data in the form of spark transforms. After that, I saved it as parquet files. When I run my program with 1GB data in 10 nodes 8GB configurations in AWS it takes about 11 min. I changed it to 20 nodes 32GB configuration. Still it takes about 10 min. Reduced only around 1 min. Why this kind of behavior?   </p>