Fine-grained Middleware Composition for the Boeing NEST OEP

Transcription

1 Fine-grained Middleware Composition for the Boeing NEST OEP Venkita Subramonian,Chris Gill, Huang-Ming Huang, Stephen Torri Washington University, St. Louis Jeanna Gossett, Tom Corcoran, Douglas Stuart The Boeing Company, St. Louis {jeanna.m.gossett, Research Supported under the NEST program DARPA contract F C-1898 with AFRL 1

2 Topics NEST overview Boeing OEP overview and architecture Motivation for norb Relationship of CORBA to norb norb components Future work 2

3 NEST overview Networked Embedded Software Technology Distributed Real-Time system with 100 to 100,000 networked nodes Resource constrained hardware components Requires fine-grained fusion of hardware and software components Applications in advanced avionics and space systems, weapon systems, wireless devices 3

4 NEST middleware services Real-time Coordination Services Fault tolerance Data exchange Synchronization Self-stabilizing protocols Replication Automated synthesis of services 4

5 Boeing NEST OEP Acoustic and Structural Damping Configuration Plant model -.2hz System Identification Control Parameters Group Status Ping Command Node Health and Parameters New Group Ping Sensor and -.2hz Configuration 100 hz Actuator -1 hz Data -.2 hz Group Control Group Control Group Control Ping Command and Parameters -.2hz Ping Sensor and Control Parameters Actuator -1hz Data -.2 hz Health 100 hz Low Level Ping An input to stimulate Control the fairing s structural Control Loop vibration modes. 2Khz Sensor Actuator 5

6 Boeing OEP architecture Application Components Configuration System Identification Group Control Low Level Control Domain Services Clock Synchronization Scheduling Group Communication System Services Constraint Satisfaction Group Management Dispatch Time Service Discovery Naming NEST ORB NEST subset of ACE Operating System 6

7 Why Not a Full CORBA ORB? Mis-match with the NEST Domain Most ORB features not necessary in NEST Application specificity is a key issue Limited number of objects in NEST Scalability in terms of number of nodes not number of objects per node Footprint constraints 7

8 Motivation for norb Provide primitives for NEST middleware and services Limit communication middleware features to application requirements Reduce footprint Assure Timeliness, Support Adaptation Top-down approach very difficult, prolonged, and error-prone to achieve More minimal than minimum-corba 8

9 Ubicore Related work Framework to hide different middleware protocols like IIOP, COM, Java RMI Generic request broker for hand-held devices MicroQoSCORBA CASE-tool based approach to middleware customization/composition Prototyped in Java 9

10 CORBA-ness of norb GIOP messages Request, Reply, Locate request, Locate reply Object Adapter, albeit a very simple one Remote Object References IDL compiler generated stubs and skeletons Limited form of Exception support 10

11 registerobject() resolvereference() objecttostring() stringtoobject() init() run() shutdown() norb interface 11

12 norb - Under the hood ACE - Adapative Communication Environment Highly efficient, portable primitive components ACE components used in NEST Reactor, Timer, Threads, Acceptor, Connector, CDRStream Further decomposition of ACE primitives on an as-needed basis. 12

13 Towards a Fine-Grained ACE_Event_Handler ACE_Service_Object ACE_Task_Base ACE_Task ACE_Svc_Handler Substrate ACE_Event_Handler PS_Event_Handler Peer stream Decoupling concerns Reactor Acceptor Connector Event Handler Svc Handler Task 13

14 norb Dispatcher Based on Kokyu Scheduling Framework Adaptive Scheduling in NEST Scheduler as a middleware service in NEST Dispatching infrastructure to support the scheduler Support for FIFO (RMS) Future support for different scheduling strategies EDF, MLF 14

15 Dispatcher interface initqueues() clearqueues() registerdispatchable() mergeschedule() clearschedule() dispatch() start() stop() 15

16 Future work Infrastructure Composition techniques for scheduling/dispatching Further decomposition of ACE classes to achieve additional footprint reductions Apply Generative/Generic/AOP techniques for customizable middleware composition norb performance metrics/optimizations 16