1. VEST Tool • Base Libraries • SW • OS • Middleware • Aspects • Domain Code • HW • Infrastructures • Configuration Tool • Browse • Compose • Check • Analysis Tools Product Library Dependency Checks Composition Map to Process Map to HW Analysis • Factual • Inter-component • Aspects • General • Real- Time • Reliability Dependency Checks Dependency Checks

2. Perspective/Design Tools Requirements Design/Design Analysis Synthesis/(Components with Analysis) VEST

3. VEST Underlying Models -Tailored to Bold Stroke • Concurrency – Event Channels • Scheduling - TAO real-time scheduling service • Persistence

4. Persistence Filter/correlation scheduler Real-time Fault-tolerance Functional code priority queue dispatcher Select from library VEST Design Avionics code Mapping Supplier1 E1 Libraries ES1 Consumer1 Event Channel Supplier2 E2 App lib ES1 Consumer2 E3 Supplier3 persistent data schedulers Event Channel Middleware dispatchers real-time aspects fault-tolerant aspects ORB MW lib OS lib OS periodic-save thread supplier threads dispatcher threads HW lib CPU1 CPU2 EEPROM HW

5. consumer consumer consumer Task Model and Events • N supplier threads {STi} and events {EVi}: • STi and EVi has a specified rate STj • M dispatcher threads {DTj} and event-set priority queues {Qj} • One dispatcher thread for each priority queue Event Channel push(ev) push(ev) Filtering Correlation Scheduler Supplier/POA threads priority queues dispatcher threads Events

6. RT Schedulability Analysis • Integrated schedulability analysis for Bold Stroke • Event suppliers/consumers • Event channels • Persistent service • ORB core • Support tailoring Bold Stroke for timing requirements • Select/configure scheduling algorithm • Select/configure dispatching mechanism • Support for inter-processor events • Expand scheduling analysis to new situations

7. Real-Time Scheduling Analysis Spring Scheduling model • TAO RT Sch. • Service • resources • events • precedence • overheads EDF (Stankovic, et. al. Text) TimeWiz (RMA)

8. RT Scheduling Analysis Ideas • EDF with precedence and resources • utilization bounds • Hierarchical scheduling with guarantees • critical and essential tasks • based on results in Regehr’s thesis • Statistical guarantees • feedback control real-time scheduling

9. Aspects • Defining/understanding language independent aspects • Vanderbilt -> constraints • UVA • cross cutting dependency checks • EX: Buffer sizing • how to change components • EX: Replication of critical data

10. Next slide is just for your information • You do have something on experiments – I’m sure Doug will ask about that so you may think about it in more depth, e.g., like I have on the next slide (but that is not very deep either)

11. Longer Term Plans • Experiment 1 • modify persistence requirements (example: save rates, redundancy, security levels) • levels of scheduling requirements • critical and essential tasks • Experiment 2 • add new capability (example: automatic replication, finer grain locking) • levels of scheduling requirements • statistical guarantees