> If on a TaskTracker, the maximum limit of tasks is set to N, N > parallel tasks may be run on it. The N is set to two by default (since > most machines today are 2+ core'd). You can tweak this parameter to > reflect one, and then you'll see only a maximum of one Task running on > the TaskTracker at a given time.
Depending on data locality, however, that could actually make things run more slowly. (In principle, anyway; I don't have even anecdotal evidence to back that up. :-) I'm sure one could construct a particular set of hardware with a particular data layout for which it would be true, though.) Greg
