Mention what is the hadoop mapreduce apis contract for a key and value class?
Explain what combiners are and when you should use a combiner in a mapreduce job?
What is the function of mapreduce partitioner?
What combiners are and when you should use a combiner in a mapreduce job?
Explain what is “map” and what is "reducer" in hadoop?
Explain what does the conf.setmapper class do?
Explain what are the basic parameters of a mapper?
Mention what is the next step after mapper or maptask?
Explain what is shuffling in mapreduce?
Explain what is distributed cache in mapreduce framework?
Mention what are the main configuration parameters that user need to specify to run mapreduce job?
Explain what is the function of mapreduce partitioner?
Explain what is heartbeat in hdfs?
Explain what is a difference between an input split and hdfs block?
Explain how indexing in hdfs is done?