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MapReduce >> mail # user >> Re: 2 Map tasks running for a small input file


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Re: 2 Map tasks running for a small input file
Hi
Here is the input file for the wordcount job:
******************

Hi This is a simple test.
Hi Hadoop how r u.
Hello Hello.
Hi Hi.
Hadoop Hadoop Welcome.
******************
After running the wordcount successfully 
here r the counters info:

***************
Job Counters SLOTS_MILLIS_MAPS 0 0 8,386
Launched reduce tasks 0 0 1
Total time spent by all reduces waiting after reserving slots (ms) 0 0 0
Total time spent by all maps waiting after reserving slots (ms) 0 0 0
Launched map tasks 0 0 2
Data-local map tasks 0 0 2
SLOTS_MILLIS_REDUCES 0 0 9,199
***************

My question why r there 2 launched map tasks when i have only a small file.
Per my understanding it is only 1 block.
and should be only 1 split.
Then for each line a map computation should occur
but it shows 2 map tasks.
Please let me know.
Thanks
Sai
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB