1. UK e-Science All Hands Meeting 2005 Paul Groth, Simon Miles, Luc Moreau

2. UK e-Science All Hands Meeting 2005 Outline  Process Documentation for Provenance  Power of the P-Structure  P-assertion Recording Protocol  PReServ’s Functionality  Performance  Pitch

3. UK e-Science All Hands Meeting 2005 Provenance  The Provenance Question –Lots of definitions… –Boil it down to a question. –What is the process that led to a particular result?  How do we answer this question? –Search through documentation.

4. UK e-Science All Hands Meeting 2005 Documentation  Process Documentation –encompasses all other documentation  SOA based model of process  Actors communicate via message passing  Actors make ASSERTIONS to document process. Termed p-assertions.  How to organise these p-assertions

5. UK e-Science All Hands Meeting 2005 P-Structure

6. UK e-Science All Hands Meeting 2005 P-Structure View

7. UK e-Science All Hands Meeting 2005 Benefits  Domain independent queries  That are provenance specific  P-structure is a shared logical organisation of p-assertions  Does not prescribe how p-assertions are exactly stored in an implementation.

8. UK e-Science All Hands Meeting 2005 PReP  Introduces the Provenance Store –A Separate entity for maintaining process documentation  PReP specifies how an actor can communicate with the Provenance Store.  PReP has a number of nice properties. – Statelessness – Idempotence – Terminiation

9. UK e-Science All Hands Meeting 2005 An Implementation  What is PReServ? –A Web Services implementation of a Provenance Store –Implements PReP for recording XQuery for querying –Provides libraries and wrappers for making applications provenance aware.

10. UK e-Science All Hands Meeting 2005 Axis Handler Axis Handler Provenance Store Backend Store Interface Database Store In-Memory Store … Backend Stores PS Client Side Library PS Client Side Library Web Service WS Client Query Actor WS PS Client Side Library WS Calls Java Calls PReServ Implementation Diagram

11. UK e-Science All Hands Meeting 2005 Implementation cont. Backend Store Interface Java Object DatabaseMemory… Store Plug InQuery Plug In … Dispatcher SOAP Msg  Caching mechanism to improve performance  Berkeley Java Database 2.0 No setup required Completely Transactional

12. UK e-Science All Hands Meeting 2005 Requirements  Apache Tomcat 5.0  Apache Ant 1.6.2  Java 1.5 (1.4 supported with some help)  Pure Java, tested on –Windows –Mac OS X –Debian Linux

13. UK e-Science All Hands Meeting 2005 Evaluation Deployment  Protein Compressibility Experiment –HPDC’05  Workflow runs under VMWare –deployment consistency –ease of development  Workflow is executed on one machine  PReServ runs on another machine –Version 0.1.5 of PReServ

14. UK e-Science All Hands Meeting 2005 Record Performance

15. UK e-Science All Hands Meeting 2005 Query Performance

16. UK e-Science All Hands Meeting 2005 Applications

17. UK e-Science All Hands Meeting 2005 Conclusion  The p-structure allows for domain independent, provenance specific queries using XQuery.  Both recording and query times are linear  PReServ has a extensible architecture allowing for further functionality to be easily added.

18. UK e-Science All Hands Meeting 2005 Download!  Try it out!  Download PReServ 0.2: –The AHM release –Released under Open Source MIT License  www.pasoa.org –Click software  Contact us, we will try to help you make your application provenance-aware.

19. UK e-Science All Hands Meeting 2005 Configuration  Redhat Linux 9.1 on VMWare on Windows XP  Pentium P4 2.8 GHZ 1.5 GB RAM  PReServ on another machine –Database backend Berkley JDB  100 Mb local ethernet