On Fri, May 7, 2010 at 2:44 PM, Jonathan Ellis <jbel...@gmail.com> wrote: > Sounds like you need to configure Hadoop to not create a whole bunch > of Map tasks at once
interesting, from a quick check it seems there are a dozen threads running. Yet , setNumMapTasks seems to be deprecated (together with JobConf) and while I guess -Dmapred.map.tasks=N may still work, it seems that so it seems the only way to manage the number of map tasks is via a custom subclass of ColumnFamilyInputFormat. But of course you have a point that in a single box this does not add anything.