Grid Quality of Service and Service Level Agreements

1
Grid Quality of Service and Service Level
Agreements

• Karim Djemame
• University of Leeds

2
Outline

• SLA What is in it?
• SLA Management Architecture
• Example SLA for a Compute Service
• Need for Resource Brokering
• Conclusion and Future Work

3
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
Purpose
Provider
3rd Parties
Parties
Consumer
Scope
SLIndicator
SLObjectives
Measurement
State
Violations
Exclusions
Policing
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DAME Problem Scenario

HTTPS
Globus GT 3
Internet
Specialist Resources
HTTPS
Consumer
Resources Grid Services White Rose Grid
Provider
5
Proposed SLA Management Architecture

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SLA Management Interaction

Interface
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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

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Example SLA for a Compute Service
Purpose Run a Grid job with guarantees Ensure the users 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 SLAs objectives met through resource brokering
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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

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SNAP Resource Broker Architecture
TSLA Task Service Level Agreement RSLA Resource
Service Level Agreement BSLA Bind Service Level
Agreement
MatchMaker
Co-Ordinator
Dispatcher
Decision Maker
Resource Gatherer
Grid Middleware
SNAP Service Negotiation and Acquisition Protocol
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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

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References

• SLA Management in a Service Oriented
  Architecture. K. Djemame, M. Haji and J. Padgett.
  ICCSA2004, 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. IPDPS2004, Santa Fe, New
  Mexico, April 2004