Designing Grid Systems: Characteristics, Problems, and Solutions

1. The Grid System Design Liu Xiangrui Beijing Institute of Technology

2. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

3. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

4. Background • Build many grid systems. • Information Power Grid • TeraGrid • DataGrid • …… • These systems applied to different fields have same aims. • The design of an appropriate grid system is a problem.

5. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

6. Grid definition • Base：resources over multiple administrative domains. • Aim: a integrated computing environment that includes various hardware and software. • Function: provide many services, support virtual organizations, etc • Means: coordinated resource sharing

7. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

8. Grid characteristics • Coordinated resource sharing • Comprehensiveness of resources • Single system image • Various services

9. Coordinated resource sharing • Through improving resource interoperability, not primarily file exchange • In grid system, users can direct access to various resources • Users and resources can cooperate in many ways to finish a task

10. Comprehensiveness of resources • There are many classes of resources • Computational resources • Storage resources • Network resources • …… • A class of resources include many kinds of resources • Computational resources may include PCs, cluster systems and mainframe computers.

11. Single system image • In grid system, there is a uniform view of resources and system states • Resource attributes • Task execution information • …… • For users, a grid system is just a supercomputer and hides the locations, structures of resources.

12. Various services • A grid system supports many types and modes of applications to meet different kinds and levels of users' demands. • Supercomputing • Data intensive computing • Virtual observatory • ……

13. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

14. Main problems to be solved • Security • Resource sharing • Single system image • System usability

15. Security • Main requirements • Authentication, authorization • Communication protection • Integration with various local security solutions • …… • Each part includes many components • Authentication includes single sign on, delegation, user-based trust. • Adopt the comprehensive, multi-layer security solutions

16. Resource sharing • Requirement • Direct access to resources • Standard protocols and interfaces to access resources must be defined • About access to computational resources • About access to storage resources • …… • The individuality of resources must be kept • Computational resources and network resources are different classes of resources and can not have same mode to use.

17. Single system image • Main requirements • Single user GUI • Single resource view • …. • Through middleware layer • The functions of the middleware layer includes resource location, node attributes and states collection, the management of users’ tasks etc.

18. System usability • System usability means that users can use grid system easily and experience its benefit. • User GUI, such as Web • Aided tools: programming tools and many API

19. Outline • Background • Grid definition • Grid characteristics • Main problems to be solved • The function model of a grid system

20. The function model of grid

21. User assistant • Function • Provide user GUI • Receive the consignment of the user identity • Manage the global user identity • Manage user tasks • Role • On behalf of a user • Make the user free from various kinds of concrete authentication and task management

22. Security center • Function • Create and issue certificates • Manage certificates • Role • The base of the system security mechanisms. • TLS-based user authentication and communication protection can be implemented.

23. Information server • Function • Maintain a uniform view of resources and system states • Dynamically manage registration information of resources • Provide resource discovery and enquiry • Role • The base of single system image. • The information in information server is static and global, and does not include the information about the execution of tasks

24. Scheduler • Function • Automatically allocate tasks to resources to lighten the user’s burden and improve system performance • Coordinate with other schedulers when the requirements between tasks conflict • Role • Task-level scheduler, not a global scheduler • It includes many scheduling strategies and algorithms.

25. Monitor • Function • Monitor tasks according to users’ demands • Create the execution log of tasks • Detect fault • Analyze , tune and predict performance • Role • Task-level monitor • Publisher/Subscriber mechanism

26. Resource agent • Function • Manage local resources • Provide standard interfaces for resource sharing • Support many mechanisms such as resource registration and task monitor • Role • On behalf of local resources

27. Conclusion • Grid system is a complex system, so overall analysis is necessary.