А
scala> spark.conf.set("spark.sql.files.maxPartitionBytes", 1024*1024)
scala> spark.read.format("csv").option("header", "false").option("delimiter", ",").load(file).rdd.getNumPartitions
res7: Int = 14
scala> spark.conf.set("spark.sql.files.maxPartitionBytes", 1024)
scala> spark.read.format("csv").option("header", "false").option("delimiter", ",").load(file).rdd.getNumPartitions
res9: Int = 13698