Jun, On Aug 8, 2011, at 2:19 AM, 谭军 wrote: > 2 computers with 2 CPUs. > Each CPU has 2 cores. > Now I have 2 physical datanodes. > Can I get 4 physical datanodes? > I don't know wether I make my point clear?
Running multiple datanodes on the same machine really doesn't buy you anything - the underlying storage is just partitioned. OTOH, if you just want to simulate a larger cluster you'll need to setup 2 different HADOOP_HOME, configs etc. and also need to ensure ports don't clash. Same for running multiple tasktrackers on same node - again, only makes sense while simulating. hth, Arun
