Re: Does a Map task run 3 times on 3 TTs or just once

[Sai Sai]

Just wondering if it is right to assume that a Map task is run 3 times on 3 
different TTs in parallel and whoever completes processing the task first that 
output is picked up and written to intermediate location.
Or is it true that a map task even though its data is replicated 3 times will 
run only once and other 2 will be on the stand by just incase this fails the 
second one will run followed by 3rd one if the 2nd Mapper fails.
Plesae pour some light.
Thanks
Sai