In a preferred embodiment, the present invention is an asymmetric data
processing system having two or more groups of processors that have
attributes that are optimized for their assigned functions. A first
processor group, which may be SMP machines, are responsible for
interfacing with applications and/or end users to obtain queries, and for
planning query execution. A second processor group consists of many
streaming record-oriented processors called Job Processing Units (JPUs),
typically arranged as an MPP structure. The JPUs carry out the bulk of
the data processing required to implement the logic of a query, running
autonomously and asynchronously from other processors in the system. The
JPUs preferably use a multi-tasking operating system that permits
multiple tasks to run at a given instant in time, in either an
absolute-priority-based or a weighted-priority-based demand scheduling
environment.