XtremWeb: Building an Experimental Platform for Global Computing Gilles Fedak, Cécile Germain,

1. XtremWeb: Building an Experimental Platform for Global Computing Gilles Fedak, Cécile Germain, Vincent Néri, Franck Cappello Université Paris Sud, LRI, FRANCE Parallel Architecture Team « Cluster and Grid » group

2. Outline Motivations and Goals for XtremWeb Use example and applications. Inside XtremWeb. Conclusion.

3. XtremWeb Objective Using PCs connected to Internet during their idle time XtremWebWork Server LRI X * 1000 volunteers PCs Internet XtremWeb Result Collector LRI? A platform to investigate Global Computing and Peer to Peer system issues

4. Global Computing Global Computing : cycle stealing on a very large number of unused computing resources over Internet. • Massively Distributed Applications • SETI@Home, distributed.net • 2.5 Millions users, 30 TFLOPS • Research Projects • Javelin, Bayanihan, JET, Charlotte • Ongoing Projects • Entropia, Parabon, Peer to Peer WG • Folding@Home, Xpulsar@Home

5. Peer to Peer Peer to Peer : Global Client/Server resources and services sharing over Internet. • Massively distributed applications • Napster, Gnutella, Freenet, etc. • Large number fo users ~x Millions, Stockage area in the TeraByte order • Research Projects • Globe (Tann.) Cx (Javelin), OceanStore (USA) XtremWeb (LRI) • AppLeS (UCSD) • On going projects • Cosm, Wos, peer2peer.org, Jxta P2PTL (Intel) CoG (Globus). • Conference • O’Reilly • Book • Peer to Peer, «Harnessing the Power of Disruptive Technologies » Andy Oram, O’Reilly

6. Desired Properties. • Computing models. • Global Computing. • Peer to Peer. • Multi-applications • Native code execution. • Worker safety. • High performance • Scalable and dedicated server. • Multi protocol communication. • Open source • For research on global computing. • Multi-disciplinary, for production by the mean of global computing.

7. Architecture • Global Computing and Peer to Peer • 3 entities : client/server/worker • Centralized (hierarchic) GC Model PC Worker PCs Server XW Global Computing (client) PCs Server XW Peer to Peer P2P Model PC Client/Worker PC Client Internet or LAN PC Worker PC Worker

8. Application example:Pierre Auger Observatory • Project AUGER: Understanding very • high energy cosmic rays (1020 ev) • Physicists are unable to reproduce them on earth. • 1 rays every century per Km2. • Possible origin : galaxies collision. • building 2 very large detectors in south and north America • simulate a huge number of rays entering • the atmosphere (air showers) and compare them with • detectors measurements. Aires application needs a considerable computing power to calculate a very large set of independent simulations

9. Application example:Pierre Auger Observatory PC server • Aires: Air Showers Extended Simulation • Monte Carlo, Sequential, Multi parameters • time for a run 5 to 10 hours PC worker Internet air shower PC worker Aires

10. Application example:Pierre Auger Observatory

11. volonteers can evaluate their contribution to the computing effort. Worker Interface Application example:Pierre Auger Observatory

12. Another application example:Peer to Peer Ray Tracing Peer to Peer PovRay: Using the standard PovRay program (unmodified) Goal : Anyone can submit a scene and obtain the resulting image. PC Client/Worker PovRay Internet or Intranet PC Server PovRay PovRay installed on every computer Ray tracing service PC Client/Worker PovRay

13. Multiple Workers Protocol workAlive hostRegister Worker Server • Workers Initiate Transactions • Worker registers to server with hostRegister. • When unused, worker emits getWork. • Server sends parameters of the task. • While computing, worker emits workAlive • Server manages timeout on workAlive • At the end of the computation, worker sends back its results trough workResult WorkRequest workResult

14. Worker Architecture 1 thread 2 threads 5 threads • Screen saver for desktop computer • CPU Activity for nodes of processors farm Thread daemon Thread Activity Monitor Thread Activity Monitor Control Thread Thread Work Request Application Finished Thread alive Worker Mode User Mode

15. Server Architecture Database Applications Tasks Results Accounting Scheduler Communication Layer XML-RPC TCP SSL Http Server Dispatcher tasks host Workers incoming requests Users incoming requests

16. Application integration • Registering application. • Providing binaries for different runtime (OS and CPU). • Application execution grain. • parameters and results size. • and why not, a submission interface.

17. Implementation /technologies Data Base Server MySQL PerlDBI Java JDBC Java JNI XML-RPC SSL PHP3-4 GNU autotool Perl OO Gtk-Perl Communication protocol Http Server UserInterface Installation Pre requisite for installation: database (Mysql), web server (apache), PHP, JAVA virtual machine.

18. Status and Future Works • First version (Beta) • Free License (GPL) • code on cvs repository, code stabilization. • Future work. • Benchmarking and monitoring. • Lightweight worker for mobile device. • Inter worker communication. • Collaboration • Electrical and Computer Engineering Department of Toronto University. • Wuhan University (China).

19. Conclusion • Objective: • a platform for experimenting on global computing issues. • Architecture design • high performance • scalability and fault tolerance • large number of users (Personal Computer & Personal Devices) • Auger Observatory • MyXtremWeb Program • Collaborators set up their own Global Application. www.XtremWeb.net