sw components in resource constraint...

CHARLES UNIVERSITY IN PRAGUE

http://d3s.mff.cuni.cz

faculty of mathematics and physics

SW Components in Resource Constraint

Environments

Tomas Pop Tomas.Pop@d3s.mff.cuni.cz

Resource Constraint Environment

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 2

Embedded devices

Control systems

Mobile devices

Very important domain

Anywhere

Plenty of constraints

Memory, CPU

Timing (RT systems)

Battery consumption…

Why NOT to Use Monolithic Approach?

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 3

Control systems

Mission critical

Complexity is growing exponentially

Hard to validate and test

Specific hardware

Hard to reuse

=> Component based approach

How Can Components Help?

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 4

System Verification

Single components

System composition

Reuse

Specific components for specific hardware

Repository

Model lines

Overcoming system limitations

Code migration

Two Approaches

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 5

1. Systems with low requirements

Low memory footprint & CPU consumption

Association with properties (e.g. timing)

=> SOFA HI

2. Component migration

If resource is not available here, run component on server

Memory footprint

Battery consumption

SOFA HI

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 6

Profile of SOFA 2

Explicit support for real-time applications

Active and passive component

~ tasks and the others

Tool support

SOFA HI IDE

Next Steps – Executional Modes

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 7

Typical for control systems

Calibration, run, clean-up, error recovery, …

Support in existing tools (e.g. Scade)

Protocols for mode switches

Next Steps – System Models

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 8

Lot of code is generated

On another idea level than development

=> Models and simulations

Give a quick view how constructed system works

Component Migration - Motivation

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 9

Targeted to cell phones and tablets

Conditions there are changing rapidly

Lot of users, often connected to internet via wifi…

Limit is not memory and CPU anymore

Limit is battery consumption

Processor is consuming major portion of energy

Wide range of application similar architecture

SENSOR – COMPUTATION – DISPALYER

Component Migration - Usage

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 10

Lets migrate processor intensive parts to a server

If sufficient network connection is available

Only parts not bounded to hardware

In network is not available, executed locally

Different to cloud computing

Component Migration - Example

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 11

Voice recognition

Microphone driver component stays on the phone

Recognition executed on remote server

Text displayed/saved on the phone

Component migration – Plan

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 12

Measurements

Simple component model

Metrics for code offload decisions

Implementation

Evaluation

Thank You

Tomas Pop | Res Informatica Seminar | 2.11.2010 Components in Resouce Constraint Environments 13