It is stated that the default zstd compression level is 1 in Spark documentation. https://spark.apache.org/docs/latest/configuration.html
I set this property to different values both in spark-defaults.conf,
and inside the code like
val conf = new SparkConf(false)
conf.set("spark.io.compression.zstd.level", "22")
val spark = SparkSession.builder.config(conf).getOrCreate()
..
Reading same input and saving/writing it in parquet format with zstd compression multiple times did not change the output file size at all. How can one adjust this compression level in Spark?