Overview CS -Framework

1. Overview CS-Framework Introduction (Over)view Lessons Learned CS-Workshop 2011, Dietrich Beck

2. Control System Control devices (power supplies, function generators, timing, complex experimental procedure…) No process control DAQ and data processing is only a minor issue Integrate things that were not developed to work together as a system Ever changing set-up The same experiment is never done twice Reconfiguration of complete hardware (seconds!) Integration of new hardware (next beam-time) Small and medium size experiments No dedicated staff for control systems Different experiments but similar problems to solve (configuration, complex timing schemes, similar hardware,…) …  What about a “Framework”? Starting Point (2001) CS-Workshop 2011, Dietrich Beck

3. Wikipedia: “…a software framework is an abstraction in which common code providing generic functionality can be selectively overridden or specialized by user code, thus providing specific functionality…” Common Code – Standardization re-usability of software components maintainability of software components same look and feel at different experiments ease transfer of know-how User Code - Specialization concentrates on experiment specific requirements extension of framework, specializing code "Framework" CS-Workshop 2011, Dietrich Beck

4. Developer: User: picture pocket knife ... a tool box ... something ready to use (sth. to solve a problem) without additional work (= the solution!) Different Points of View – A Framework is... CS-Workshop 2011, Dietrich Beck

5. control system = framework + add-ons GUI Cycle Control HV Timing+DAQ AFG Definition of the CS-Framework add-ons may become part of framework bug reports, new features requested experiment EE/KS and contributors bug fixes, new features, maintenance CS-Workshop 2011, Dietrich Beck

6. SIS Z6 HHT UNILAC PHELIX PHELIX (Petawatt High-Energy Laser for Heavy Ion Experiments) Up to 3 MJ electrical energy converted to 1kJ light energy or 0.5 Petewatt laser power. 2300 documented “shots” (Dec. 2010). About 10k process variables distributed on 15+ nodes in 2 buildings (slide by S. Götte, GSI) CS-Workshop 2011, Dietrich Beck

7. Quad-Triple Trap Mass Spectrometer ISOLTRAPHigh-precision mass determination of unstable nuclei with a Penning trap mass spectrometer at ISOLDE/CERN www.cern.ch/isoltrap • Nuclear-, Astro-, Fundamental Physics • m/m  10-8 (typically!) • via cyclotron frequency of stored ions • “sub-µs ion-juggling” every second CS-Workshop 2011, Dietrich Beck

8. One development tool  LabVIEW Standardization  object oriented approach, base classes Distribution to many nodes  DIM (www.cern.ch/dim) Event driven communication for everything Scaling to large systems by distribution Remote access … SCADA functionality (alarming, trending, …)  LabVIEW DSC module Cooking Recipe for the CS Framework CS-Workshop 2011, Dietrich Beck

9. DIM (www.cern.ch/dim) Peer-to-peer connection, no intrinsic bottle neck Named service as concept (a name server aids in setting up connections) “service”: publisher-subscriber-pattern, one-to-many “command service”: command-pattern, many-to-one CS objects communicate via DIM services: publishing/subscribing to state information DIM commands: triggering actions synchronous commands (timeout, “expire date”,…) everybody may talk to everybody Events provide the interface between device object and it’s GUI object device object and application layer hierarchical state machines … Design Approach - First: communication layer, Second: framework Connectivity to other programming languages and OSs Back-end (SCADA, GUI, ...) Middleware (communication,.) Front-end (devices, drivers, ...) 3-layers Event Driven Communication Caller Callee CS-Workshop 2011, Dietrich Beck

10. "BaseClass" provides basic functionality (communication layer, active threads, ...) "DeviceClass" adds functionality according to specs of device type "DS345". Instantiation: one object per device Object Orientation (OO) with CS "BaseClass" inheritance "Device Class" AFG3 AFG1 AFG2 • of course: classes for GUIs, Sequencer, State machines, ... • OO implemented by CS using pure LabVIEW (no LVOOP) CS-Workshop 2011, Dietrich Beck

11. _birthday, time/date of creation _classID, class name _condition, object created successfully… _systemID, name of (sub)system _accessID, reservation mechanism... _evtCounter, number of cmds received status of threads… Ping, thread alive? GetDescriptors (Introspection!!!) Reset (override by child classes) … _deviceGUI, name of GUI class Initialize, init interface _deviceID, ID string of device Close, close interface _deviceState, OK, ERROR, … IDQuery, query device ID … … _nomFrequency, frequency set-value SetFrequency, sets nominal value _actFrequency, frequency get-value GetFrequency, gets actual value … … CSObj THE base class CAEObj send/rec. events BaseProcess threads for events and periodic action DeviceBase basic device properties AFGBase arbitrary function generator… Standardization of Services and Cmds CS-Workshop 2011, Dietrich Beck

12. (Over)view CS-Framework Introduction (Over)view Lessons Learned CS-Workshop 2011, Dietrich Beck

13. SourceForge: downloads, tracker (bugs, features,…) CS-Workshop 2011, Dietrich Beck

14. SCC via SubVersion @ GSI CS-Workshop 2011, Dietrich Beck

15. Domain Management System: Process Management in a Distributed Environment CS-Workshop 2011, Dietrich Beck

16. Process Monitoring CS-Workshop 2011, Dietrich Beck

17. Packaging CS-Workshop 2011, Dietrich Beck

18. Documentation via Wiki CS-Workshop 2011, Dietrich Beck

19. Class Documentation via UML Tools CS-Workshop 2011, Dietrich Beck

20. Status CS-Framework Introduction Over(view) Lessons Learned CS-Workshop 2011, Dietrich Beck

21. Stress Field of the Responsible Person: The OS (XP) and/or the intranet are always unreliable, the programming language (LabVIEW) never really fulfills the need, the framework (CS) is only close to the requirement, the classes of other CS collaborators are typically not usable, there is no way to test things since there is no test system available while the real system is always in use, the users never define what the program has to do, but are not pleased with what the programmer delivers, and they misuse the system additionally. Anyhow: The goal is an easy system where the happy user does not realize what happens behind the scene, which works reliable and for ever (better: till the next LabVIEW version is installed). Lessons Learned – What Users say about CS(from a talk by Stefan Götte, at the NI BIG PHYSICS Round Table, Paris, 2009) CS-Workshop 2011, Dietrich Beck

22. Design principles of major importance A control system must be designed to crash and (auto-)recover from failures of all kinds Fileserver down Computer down/reboot Installation of updates Switched-Off/On by users … Network down Power cuts … The system is stressed most, when everything goes wrong (failures, alarms, sub-system crash…) and all kinds of asynchronous signals fire at the same time (self-induced DoS-Attack) and availability is most important. “The OS (XP) and/or the intranet are always unreliable” (assumption for design phase) CS-Workshop 2011, Dietrich Beck

23. Stress Field of the Responsible Person: The OS (XP) and/or the intranet are always unreliable, the programming language (LabVIEW) never really fulfills the need, the framework (CS) is only close to the requirement, the classes of other CS collaborators are typically not usable, there is no way to test things since there is no test system available while the real system is always in use, the users never define what the program has to do, but are not pleased with what the programmer delivers, and they misuse the system additionally. Anyhow: The goal is an easy system where the happy user does not realize what happens behind the scene, which works reliable and for ever (better: till the next LabVIEW version is installed). Lessons Learned – What Users say about CS(from a talk by Stefan Götte, at the NI BIG PHYSICS Round Table, Paris, 2009) CS-Workshop 2011, Dietrich Beck

24. The fundamental problem about documentation Two lines of text are not enough, but Two pages of docs – (almost) nobody will read that* Docs out of date … Solutions HOW-TOs, FAQs Auto-generated documentation Class documentation, CS2JavaUML Requires well documented code (again: coding conventions!) Release notes Demo-system (delayed…) * sometimes not even the first two lines… Lessons Learned - Documentation CS-Workshop 2011, Dietrich Beck

25. Generic tools (generic control system GUI, generic device GUIs) Sometimes difficult to understand ( documentation problem) Lot’s of work to maintain Don’t match the users’ needs exactly Either least common denominator (missing features), or include all requested features (too complex) “Nobody likes them, but everybody uses them.” Lessons Learned – Generic/Common Tools CS-Workshop 2011, Dietrich Beck

26. Identifying missing features sometimes requires telepathic skills results in cool solutions that are finally not used (nice to have versus really useful) CS Access System Sequencer ObjectNets, PetriNets some base classes … Lessons Learned – Missing Features CS-Workshop 2011, Dietrich Beck

27. Backward Compatibility (“does my old code still work?”) Is maybe THE most important feature of a framework Often results in a impressive mix of different versions (core system v1, base classes v2, GUI v4, device classes v3,…) Makes it hard to correct wrong design decisions Requires clear public library routines or class methods, but… using conventions on what is public/private does not work Lessons Learned – Compatibility CS-Workshop 2011, Dietrich Beck

28. Wikipedia: “…software frameworks … reducing overall development time” (?) Amount of time for solving a problem decreases dramatically, if a problem may be solved with (generic) existing software. “configuration instead of coding” does not change – but the solution is much better may even increase (short-term), compared to a dedicated solution not (!) using the framework (required: training, courses, understanding and application of conventions) decreases (long-term): framework maintained by others, re-usability of code, replacing hardware, coding conventions enforced, maintainability, common language, know-how transfer, … Lessons Learned – The “Saving-Time-Myth” CS-Workshop 2011, Dietrich Beck

29. require high flexibility have a large variety of hardware types have up to 10,000 (1M possible) process variables require fast ( 100 ns) timing control using dedicated hardware PHELIX SHIPTRAP ISOLTRAP LEBIT POLARIS, HIJ others ... Motion CaveA data taking Motion CaveA HITRAP commissioning REXTRAP FOPI development Experiments using the CS framework... RISING ClusterTRAP LPT GSI, Germany Mainz, Germany Greifswald, Germany CERN, Switzerland MSU, USA Lanzhou, China TrigaTRAP CS-Workshop 2011, Dietrich Beck

30. CS 3.21 released for LV2009. about 15 active applications 1,000,000 PVs demonstrated, an even larger number should be feasible 5,000 objects ( hardware devices) demonstrated, an even larger number should be feasible stability of a distributed CS system is better than a few hundred hours of continuous operation about 15 (60) hardware devices supported on SourceForge (Subversion) FAIR: MATS and parts of HITRAP have selected CS as control system framework. Conclusion and Outlook CS-Workshop 2011, Dietrich Beck

31. Holger Brand, Dietrich Beck, Mathias Richter, Alexander Schwinn, Falk Ziegler, Romain Savreux, Chabouh Yazidjian, Klaus Blaum, Dennis Neidherr, Melanie Wolf, Stefan Schwarz, Josh Savory, Stefan Götte, Maximilian Kugler, Tobias Habermann, Michael Block, Frank Herfurth, Christian Rauth, Stephen Koszudowski, Manas Mukherjee, Thomas Rechel, Martin Feldmann, IT@GSI, ……………... Acknowledgements... CS-Workshop 2011, Dietrich Beck