Download - Green Architectural Tactics for the Cloud @WICSA 2014

Green Architectural Tactics for the Cloud

Giuseppe Procaccianti

Patricia Lago

Grace A. Lewis

A common statement


“Cloud computing is

energy efficient...”

Cloud as a Nation

...but how much, exactly?


Our approach

Energy Efficiency as a Software quality attribute


● Software determines hardware behavior

● We can design scenarios about energy efficiency

Our approach /2

Cloud Service

We analyze Software Architectures to study their influence on Energy Efficiency.

Energy Efficiency in Cloud Software Architectures


What is a Tactic?

“A design decision that influences the achievement of a

quality attribute response.” [1]

[1] L. Bass, P. Clements, and R. Kazman, Software architecture in practice, ed. Addison-Wesley, 2012.



● 3 categories:

1. Energy Monitoring

2. Self-Adaptation

3. Cloud Federation

● Elicited from a SLR on Cloud-based software architectures [2]


[2] G. Procaccianti, P. Lago, S. Bevini. “Green Software Architectures in the Cloud”. Submitted to Sustainable Computing (SUSCOM), Special Issue on Software Engineering Aspects of Green Computing (SEAGC), 2014.

● Scenarios for Energy Efficiency [1]



Energy Monitoring

Metering

Modeling

Static Classification

Self-Adaptation

Scaling Down

Consolidation

Workload Scheduling

Cloud FederationEnergy Brokering

Service Adaptation


2. Self Adaptation

● Stimulus: Excessive energy consumption alert

● Source of Stimulus: Energy Monitor

● Environment: Runtime

● Artifact: Hypervisor

● Response: The Hypervisor consolidates the VMs on the

less-active servers and then shuts down the idle servers.

● Response Measure: Energy consumption values




Energy Monitoring

Metering

Modeling

Static Classification

Self-Adaptation

Scaling Down

Consolidation

Workload Scheduling

Cloud FederationEnergy Brokering

Service Adaptation


Self Adaptation tactic: Consolidation

(Implementation example)


Discussion

● ...pose assumptions and constraints on the software architecture

● ...introduce a trade-off between EE and other system qualities

● …exhibit dependencies between each other and, in general, they cannot be applied in isolation

The Green Architectural Tactics are nice, but….


What’s next?

Inclusion of EE in a Software Quality

Model, for design-level decision-making

Evaluation of the environmental impact of Cloud-based software


Thank you!
