1. www.eu-eela.eu 1 Bogotá, EELA-2 1 st Conference, 25.02.2009 The OurGrid Approach for Opportunistic Grid Computing Francisco Brasileiro Universidade Federal de Campina Grande – UFCG fubica@dsc.ufcg.edu.br E-science grid facility for Europe and Latin America

2. www.eu-eela.eu 2 Bogotá, EELA-2 1 st Conference, 25.02.2009 Motivation Several initiatives have already proven the potential of opportunistic grids to deliver high-throughput computing –Volunteer computing  SETI@home uses idle cycles of resources in the Internet leaves  Folding@home uses (among other resources) idle cycles in gaming devices –Desktop grids  Condor pools use idle cycles of the desktops connected in LAN  Pools can be federated in a “flock of Condors”

3. www.eu-eela.eu 3 Bogotá, EELA-2 1 st Conference, 25.02.2009 Motivation Drawbacks of the volunteer computing approach –Entrance barrier is high, because one must  have a very good support team to run “the server”  invest a good deal of effort in “advertising”  have a very high visibility project  be in a prestigious institution –May be useful when the organization has access to a large number of desktops  Incorporating new applications may be costly

4. www.eu-eela.eu 4 Bogotá, EELA-2 1 st Conference, 25.02.2009 Motivation Drawback of the Condor approach –Condor was first proposed to harvest the idle cycles of workstations in LANs –Flock of Condors require offline negotiation  No incentive mechanism OurGrid is a peer-to-peer alternative –Provides an incentive for the donation of resources

5. www.eu-eela.eu 5 Bogotá, EELA-2 1 st Conference, 25.02.2009 Each lab corresponds to a peer in the system and contributes with its idle resources cpu utilization for lab 1 100% real time cpu utilization for lab 2 100% real time cpu utilization for the p2p grid 100% real time Rational of a peer-to-peer grid

6. www.eu-eela.eu 6 Bogotá, EELA-2 1 st Conference, 25.02.2009 OurGrid characteristics Labs can freely join the system without any human intervention –Entrance negotiation is not mandatory due to default prioritization scheme Clear incentive to join the system –One cannot be worse off by joining the system –Noticeable increased response time –Free-riding resistant Basic dependability properties –Configurable level of security –Resilience to faults –Scalability Easy to install, configure, manage and program –No need for specialized support team

7. www.eu-eela.eu 7 Bogotá, EELA-2 1 st Conference, 25.02.2009 Architecture Thanks for your attention! Questions?

8. www.eu-eela.eu 8 Bogotá, EELA-2 1 st Conference, 25.02.2009 What kind of applications are supported by an OurGrid grid? It will depend on the virtual machines that will be made available by the managing agent of the worker nodes Currently we have support for BoT applications that: –Have relatively short tasks  Due to the best-effort nature of the worker nodes –Have no inter-task communication –Are self-contained  no need for special dynamically linked libraries

9. www.eu-eela.eu 9 Bogotá, EELA-2 1 st Conference, 25.02.2009 Rendering with OurGrid job: label: my_rendering_example requirements: (os=linux) task: init:store render $STORAGE put input-1 $PLAYPEN remote: render output-1 final: get output-1 output-1 task: init:store render $STORAGE put input-2 $PLAYPEN remote: render output-2 final: get output-2 output-2 …

10. www.eu-eela.eu 10 Bogotá, EELA-2 1 st Conference, 25.02.2009 How does OurGrid prevent free-riding? OurGrid uses a reciprocation-based incentive mechanism –Tit-for-tat The Network of Favors –All peers maintain a local balance for all known peers –Peers with greater balances have priority when there is contention for local resources –Balance never goes below zero  Newcomers and free-riders are treated equally –Under contention, the more one donates, the more one gets back –No additional infrastructure is needed

11. www.eu-eela.eu 11 Bogotá, EELA-2 1 st Conference, 25.02.2009 Epsilon is the fraction of resources consumed by free-riders Free-rider consumption

12. www.eu-eela.eu 12 Bogotá, EELA-2 1 st Conference, 25.02.2009 OurGrid security How to protect resources from applications? How to protect applications from resources? Not a “One-Size-Fits-All” solution –Portfolio of mechanisms  Authentication and prioritization Asymmetric cryptography Sub-communities  Execution isolation and authorization Virtual machine technology User-defined policies  Tolerance to application sabotage Application dependent (watermark + checking)

13. www.eu-eela.eu 13 Bogotá, EELA-2 1 st Conference, 25.02.2009 Latin America Grid 2007 13 OurGrid is fast, secure, and easy to use Joining is automatic –Just go to www.ourgrid.org and download the software –No paperwork required to join the Global Community –Simpler negotiation in other communities (eg. EELA-2) It is open-source –Contributions are welcome Supports several Grid Communities –Global Community (http://www.ourgrid.org) –ShareGrid ( http://dcs.di.unipmn.it/ ) –EELA-2 (coming soon) Many applications have already profited from OurGrid-based grids Conclusion

14. www.eu-eela.eu 14 Bogotá, EELA-2 1 st Conference, 25.02.2009 A good starting point to learn more about OurGrid is: –Labs of the world, unite!!! W. Cirne, F. Brasileiro, N. Andrade, L. Costa, A. Andrade, R. Novaes, M. Mowbray. Journal of Grid Computing 4 (3) (2006) 225-246. And meet us at www.ourgrid.org! Thanks for your attention! Questions?