1. Grid Quality of Service and Service Level Agreements Karim Djemame University of Leeds

2. Distributed Aircraft Maintenance Environment - DAME Outline SLA: What is in it? SLA Management Architecture Example: SLA for a Compute Service Need for Resource Brokering Conclusion and Future Work

3. Distributed Aircraft Maintenance Environment - DAME Service Level Agreements (SLA) A Service Level Agreement is “…an explicit statement of expectations and obligations that exist in a business relationship between two organisations: the service provider and the customer.” Formalises requirements and specifies behaviours SLA Model: SLA Root SLObjectives Parties Purpose SLIndicator Scope Exclusions Provider Consumer 3 rd Parties State Measurement Violations Policing A description of the service being provided Names of the provider, consumer and 3 rd A definition of the domains in which the SLA is valid Levels of service (guarantees) agreed on What is not covered by the SLA Describes the SLA state

4. Distributed Aircraft Maintenance Environment - DAME DAME Problem Scenario HTTPS Consumer Internet Globus GT 3 Resources + Grid Services White Rose Grid dBHPC x Specialist Resources GS x Provider User wants access to computational resources on the Grid Portal access over internet Grid resource access via Grid Services and the Globus Toolkit

5. Distributed Aircraft Maintenance Environment - DAME Proposed SLA Management Architecture Selects resources and submits the execution Reacts to violations by adapting managed grid service execution Negotiates SLA between the user and provider Monitors Service Level Objectives and records violations Provides access to service functions Provides meta-data relating to the service eg. state

6. Distributed Aircraft Maintenance Environment - DAME SLA Management Interaction Negotiate SLA Sign SLA Monitor and record violations Reserve resources Capture user requirements Adapt to violations Launch managed grid service Interface

7. Distributed Aircraft Maintenance Environment - DAME SLA Management Automated management will provide autonomic self-optimisation without the need for user intervention Outcome: for each Grid Execution instance, an SLA Manager will provide: –SLA –resource reservation –job monitoring –job adaptation –violation log

8. Distributed Aircraft Maintenance Environment - DAME Purpose Run a Grid job with guarantees Ensure the user’s requirements are met Parties The user, the broker, the resources Scope Compute service Service Level Objectives Availability of resources Attributes: CPU count, CPU type, CPU speed, RAM, Storage, Operating system and version Service Level Indicators Resource availability and value of each attribute Exclusions What is not currently supported Administration SLA’s objectives met through resource brokering Example: SLA for a Compute Service

9. Distributed Aircraft Maintenance Environment - DAME SLA Specification using XML Grid Task requirements represented in an SLA content tree (JAVA) SLA content tree converted to XML using Java Architecture for XML Binding (JAXB) SLA XML document created to interact with external resource brokers and pass user requirements

10. Distributed Aircraft Maintenance Environment - DAME Knowledge bank Matchmaker Co-ordinater Dispatcher Resource gatherer Decision maker Grid middleware RRRR TSLA BSLA Portal RRRR RSLA Portal Grid Resources SNAP Resource Broker Architecture Decision Maker Resource Gatherer Co-Ordinator Dispatcher Grid Middleware MatchMaker TSLA: Task Service Level Agreement RSLA: Resource Service Level Agreement BSLA: Bind Service Level Agreement SNAP: Service Negotiation and Acquisition Protocol

11. Distributed Aircraft Maintenance Environment - DAME Current and Future Work Implementation Produced a basic implementation of an SLA Manager to accept user requirements, embed them within an SLA (XML) document and report them back to the user SNAP-based resource broker being deployed on the WRG Automated Monitoring Engineering automated monitoring within the SLA Manager Enable subscriptions to an external Grid Monitoring Service depending on the SLA guarantees Adaptation Algorithm Investigate an adaptation algorithm that is suitable for use within a Service Oriented Architecture Integration with SLA Manager

12. Distributed Aircraft Maintenance Environment - DAME References SLA Management in a Service Oriented Architecture. K. Djemame, M. Haji and J. Padgett. ICCSA’2004, Assissi, Italy, May 2004 A SNAP-based Community Resource Broker using a Three-Phase Commit Protocol. M. Haji, P. Dew, K. Djemame and I. Gourlay. IPDPS’2004, Santa Fe, New Mexico, April 2004