1. STCM: A spatio-temporal Component Model Hinde Lilia Bouziane Christian Perez PARIS Project-Team INRIA Rennes/IRISA Toulouse, France, December 7 th 2007

2. Outline of the talk Context –Software component models and workflow languages Limitations of existing approaches for combining spatial and temporal compositions Objectives A proposal for a spatio-temporal composition model Conclusions and perspectives

3. Context Programming complex scientific applications for gird infrastructures Challenges –Simplifying application programming –Abstraction from underlying resources –Efficient usage of resources Programming by composition Today approaches –Software component models –Workflow models u PrecipitationSorption Relargage Convection Dispersion Aqueous Reactions Gaz-liquid exchange Dissolution Biology Hydrologie

4. Spatial and temporal compositions Software component models –Description approach Workflow models –Programmable approach A B C D Spatial composition t1t2 end t3 start temporal composition time y n

5. Software component models Ports –Method invocations, events/messages/streams Several component models –Common Component Architecture/CCA Forum (CCA) –CORBA Component Model/OMG (CCM) –Fractal/ObjectWeb –Service Component Architecture/OSOA group (SCA) –Etc. Software component PROVIDED PORTS REQUIRED PORTS (client interfaces) Software component (server interfaces)

6. Workflow languages Ports –Input/output data Temporal composition –Control flow and/or data flow Several languages –Askalon-Abstract Grid Wrokflow Language/ Univ. Innsbruck, Austria (AGWL) –Triana/ Univ. Cardiff, UK –Grid Concurrent Language/ HLRS Stuttgart, Germany (GriCoL) –Kepler/ SEEK, SDM, GEON, etc. –etc. task y n d_out d_in Data flow Control flow

7. Limitations of existing approaches for combining spatial and temporal compositions

8. Why combining spatial and temporal dimensions Spatial composition –Strong coupled applications –Resources usage Temporal composition –No appropriate for strong coupled applications –Resources usage

9. Limitation of existing approaches Software component models –Adding meta-data about component’s behavior (exp: ICENI) –Objective: compute an optimal placement of components –Require code knowledge –Complicate application design Workflow models –Encapsulate spatial composition within tasks implementations –Objective: offer a level of composition for coupled codes –Limits the hierarchy to two levels –Limits re-usability Limitations because of – spatial and temporal compositions are not at the same level

10. Objectives Specifying a programming model allowing both temporal and spatial composition at the same level Expressing an application behavior by the assembly Ability to deduce efficient resource usage directly from the assembly Take advantages from existing models –No need to start from scratch

11. A proposal for a spatio-temporal composition model

12. Global Approach Extending a software component –Input an output data ports –Task concept Extending a workflow language –Spatial composition to obtain an assembly language

13. Temporal port model (1/3) Component A { input double inA; output double outA; } output port input port outA A inA

14. Temporal port model: internal view (2/3) Component A { input double inA; output double outA; } output port input port outA A_implementation Container inA … void setIn_inA(double val) {…} double getOut_outA() {…}

15. Temporal port model: external view (3/3) set_double(…) outA Container Port_inA : implements Tmp_double{ void set_double (double val) {…} void connect_outA (Tmp_double p) {…} inA interface Tmp_double { void set_double(double d); void set_void(); } connect_outA(..) … void setIn_inA(...) {…} double getOut_outA() {…}

16. Task concept outA Container inA 1 impl.task() 2 4 outA.set_double() void setIn_inA(...) { d_inA =..} void task() {d_outA = d_inA + 10}; double getOut_outA() { return d_outA} set_double(25) impl.setIn_inA(25) 3 impl.getOut_outA(..) 5

17. during configuration Input reception connections Component life cycle Component states –Created –Active –Running –Inactive –Removed/no-existent created inactive active running no-existent removed task and request executions

18. Assembly model * + * condition + + ? SequenceCondition

19. Example......

20. Conclusions and perspectives Combination of spatial and temporal composition in a same programming model Extension of component model (GCM/CoreGRID) –Temporal port and task concepts Extension of workflow language (AGWL) –Spatial ports and composition Perspectives –Feasibility through an implementation Rely on a workflow engine/ dynamic deployment –Formal semantic for validation

21. Questions ?