Scheme for dynamic process network reconfiguration

摘要

Streaming applications can be represented by process networks (562), in which tasks (450, 451, 456) perform processing of data and communicate these data to each other through FIFO channels (455). During steady-state processing, the process network (562) is fixed (fixed number of tasks (450, 451, 456) and channels (455)). However, the functionality of the application may be changed at run-time implying a different process network topology. In order to avoid the run-time overhead of destroying the entire network (562) and then set up a new one, the network (562) should be dynamically reconfigured. A central task (454) manages the network topology and can issue commands to stop or suspends tasks (450, 451, 456), remove or redirect channels (455), etc. In order to avoid artefacts (e.g. processing display incomplete video frames), the tasks (450, 451, 456) respond to these commands only at certain reconfiguration points (101, 102, 103, 104) in their processing loop. By the designer these points (101, 102, 103, 104) can be freely chosen, taking into consideration the reconfiguration latency, possible partial data handling, and state cleaning.