top button
Flag Notify
    Connect to us
      Facebook Login
      Site Registration

Facebook Login
Site Registration

How does speculative execution work in Hadoop?

0 votes
How does speculative execution work in Hadoop?
posted Dec 2, 2014 by Kali Mishra

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

JobTracker makes different TaskTrackers pr2ocess same input. When tasks complete, they announce this fact to the JobTracker. Whichever copy of a task finishes first becomes the definitive copy. If other copies were executing speculatively, Hadoop tells the TaskTrackers to abandon the tasks and discard their outputs. The Reducers then receive their inputs from whichever Mapper completed successfully, first.

answer Dec 6, 2014 by Amit Kumar Pandey
Similar Questions
+1 vote

I use Hadoop 2.2 and I want to run MapReduce web UI. So I visit following url: http://x.x.x.x:50030/jobtracker.jsp

Unable to connect Firefox can't establish a connection to the server at x.x.x.x:50030. Where am I wrong?

Contact Us
+91 9880187415
#280, 3rd floor, 5th Main
6th Sector, HSR Layout
Karnataka INDIA.