i have a 2MB file, when i read it using

df = spark.read.option("inferSchema", "true").csv("hdfs:///data/ml-100k/u.data/", sep="t")

it reads data in 1 partition, and when I read using

lines = sc.textFile("hdfs:///data/ml-100k/u.data")

it reads data in 2 partitions, what is the reason?