Hi Jean, Hadoop will not factor in number of disks or directories, but rather mainly allocated free space. Hadoop will do its best to spread the data across evenly amongst the nodes. For instance, let's say you had 3 datanodes (replication factor 1) and all have allocated 10GB each, but one of the nodes split the 10GB into two directories. Now if we try to store a file that takes up 3 blocks, Hadoop will just place 1 block in each node.
Hope that helps. Regards, Robert On Fri, Dec 28, 2012 at 9:12 AM, Jean-Marc Spaggiari < jean-m...@spaggiari.org> wrote: > Hi, > > Quick question regarding hard drive space usage. > > Hadoop will distribute the data evenly on the cluster. So all the > nodes are going to receive almost the same quantity of data to store. > > Now, if on one node I have 2 directories configured, is hadoop going > to assign twice the quantity on this node? Or is each directory going > to receive half the load? > > Thanks, > > JM >
