Question

input split and block size with examples

Comments

Hi,  @Siva,

Block is the continuous location on the hard drive where data HDFS store data. In general, FileSystem stores data as a collection of blocks. In a similar way, HDFS stores each file as blocks, and distributes it across the Hadoop cluster.
 

InputSplit- InputSplit represents the data that individual Mapper will process. Further split divides into records. Each record (which is a key-value pair) will be processed by the map.
Data representation

Answer 1

Hi@siva,

Hadoop HDFS split large files into small chunks known as Blocks. It contains a minimum amount of data that can be read or write. HDFS stores each file as blocks. And input split represents the data which individual mapper processes. Thus the number of map tasks is equal to the number of input splits.