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From Iman E <hadoop_...@yahoo.com>
Subject caching in hdfs?
Date Mon, 20 Jul 2009 05:11:19 GMT
Hi,
I would like to know if hdfs do caching by default at slaves. If I ran my job twice and I
am assuming that the data is split the same way each time, is the namenode contacted everytime
to know the loaction of these files? Also, is the data read directly from disk everytime or
it can be read from the cache? I am using FSDataInputStream   to open the files and read
them.
Thanks
Iman


      
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