1. Hierarchical Reconfiguration of Dataflow Graphs Stephen Neuendorffer UC Berkeley Poster Preview May 10, 2004

2. Steve Neuendorffer - UC Berkeley 2 Dataflow Models in Ptolemy II Actors are composed to form models. Actors communicate only through ports (no shared state). Actors are strong abstractions init step factor Director specifies particular dataflow model.

3. Steve Neuendorffer - UC Berkeley 3 Dataflow Execution In general, we can think of each actor in a dataflow model as acquiring a thread. (i.e. A Process Network) But these particular components do not change dynamically: Static scheduling allows for more efficient performance. This allows for dynamic changes in the behavior of actors (i.e. reconfiguration)

4. Steve Neuendorffer - UC Berkeley 4 Approach A behavioral type theory for detecting dynamic reconfiguration. A B C ? > Static Scheduling constraint: b p c D > ? > Quasi-Static Scheduling constraint: b p c D > ? m Constraints on the least change context imply constraints on when reconfiguration occurs These constraints can be statically checked! Dynamic Scheduling constraint: b p c D > ? ?