January 8, 2015 Sam Siewert

SE300

Software Engineering Practices

Lecture 2 – Transformational

Requirements and Architecture

Motivation to Get Assignment Done

Early

Scan, Question, Read – then Complete

Start Early so You can Enjoy your Weekend!

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Learning Objective

Software Engineering Process? – Lifecycle Phases

Agile – Manifesto that Hosts Spiral, XP, Scrum, Feature-

Driven or any Iterative Process [Waterfall with Feedback]

Requirements? Architecture? – First Phase

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SPIRAL

XP - Extreme

WATERFALL

feedback

SWE Pattern – Anti-Pattern Pattern Anti-Pattern

Process Spiral Model (Risk, Effort,

Resource Control)

Mythical Man Month

Planning, Metrics, Re-

planning

Death March

Agile with XP (Extreme

Programming)

Silos

Concurrent Engineering

(HW/SW, Test/Dev)

Missed Market

Opportunity

Specification Formal, Validated Incomplete, Informal

Architecture Pattern Transformation (SIMD,

MIMD, Map-Reduce)

Sequential Processing

Design Patterns UML (Use, Behavior,

Information, States,

Interfaces) or SA/SD

Ad-hoc, pseudo-code,

Long natural language

paragraphs

Code Feature Engineering Lava Code

Structured Programming Goto, Arithmetic if

Test Regression Test Suite,

Unit Tests

Regression

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http://www.wiley.com/WileyCDA/WileyTitle/productCd-0471958697.htmlhttp://www.antipatterns.com/http://www.antipatterns.com/http://www.antipatterns.com/http://en.wikipedia.org/wiki/The_Mythical_Man-Monthhttp://en.wikipedia.org/wiki/Architectural_patternhttp://en.wikipedia.org/wiki/Software_design_patternhttps://www.doc.ic.ac.uk/~alw/edu/theses/turner-phd-0599.pdfhttp://www.antipatterns.com/lavaflow.htmhttp://en.wikipedia.org/wiki/Arithmetic_IF

Notes on Pattern Approach

Not Universally Agreed Upon as Ideal Approach to SWE – Description of Patterns – Pattern Languages

– Hard to Capture Experience

– Sheer Number of Patterns, Levels and Phases

History as a Guide, Helpful, but Not Sufficient – Avoid Common Mistakes

– Follow Best Practices

– But, Make New Mistakes

Software Engineering Institute Capability and Maturity Model – L1 – Ad-hoc

– L2 – Repeatable (E.g. Phases or Stages, Activities, Planning)

– L3 – Defined (E.g. Waterfall)

– L4 - Managed (Metrics Required – Code Coverage, Bug Rate, …)

– L5 – Optimizing (Feedback – Spiral, XP, Evolutionary)

Instructive and Can Help with Analysis Paralysis and Designer’s Block

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http://www.c2.com/cgi/wiki?PatternIndex

Software Crisis – Anti-Patterns

The Anti-Patterns for Process and Architecture Were

Noted in first 20 years of Computing (Between 1948 and

1968)

NATO Conference in 1968 – “Software Crisis”

The Idea of Engineering Software Was First Proposed at

this Conference

Similar Session on Embedded Software Systems - 2006,

Austin Texas, http://varma.ece.cmu.edu/cps/, focus on

position papers (similar to 1968 NATO Software Crisis

Conference)

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http://homepages.cs.ncl.ac.uk/brian.randell/NATO/nato1968.PDFhttp://varma.ece.cmu.edu/cps/http://varma.ece.cmu.edu/cps/

Infamous System Software Defects

Infamous & Famous Field Defects

1. Toyota ABS Software Recall, 2010

2. Windows Genuine Advantage Outage, 2006

3. Mars Climate Orbiter Units Interoperability, Loss, 1999

4. Mars Pathfinder Priority Inversion, Recovered, 1997

5. Ariane-5 501 Cluster Launch Software Failure, 1996

6. Pentium FPU Bug – Software Acceleration Co-Processor Recall, 1994

7. ATT 4ESS Upgrade, Outage, 1990

8. Therac-25 Radiation Therapy Patient Overdosing, 1985-86

9. NORAD False Alarms, User Error for Test Mode, Device Failures, 1979/1980

10. Apollo 11 Guidance Computer Overload, 1969 - Recovered

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http://en.wikipedia.org/wiki/Software_bug

RCA, Patch, Test, Fix!

http://history.nasa.gov/SP-350/ch-11-4.html

Rear Admiral Grace Hopper

http://www.computerworld.com/article/2515483/enterprise-applications/epic-failures--11-infamous-software-bugs.htmlhttp://en.wikipedia.org/wiki/2009%E2%80%9311_Toyota_vehicle_recalls#Anti-lock_brake_software_recallhttp://blogs.msdn.com/b/wga/archive/2006/10/05/wga-service-outage.aspxhttp://blogs.msdn.com/b/wga/archive/2006/10/05/wga-service-outage.aspxhttp://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_failurehttp://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_failurehttp://research.microsoft.com/en-us/um/people/mbj/mars_pathfinder/Authoritative_Account.htmlhttp://en.wikipedia.org/wiki/Cluster_(spacecraft)#Launch_failurehttp://en.wikipedia.org/wiki/Cluster_(spacecraft)#Launch_failurehttp://en.wikipedia.org/wiki/Cluster_(spacecraft)#Launch_failurehttp://en.wikipedia.org/wiki/Pentium_FDIV_bughttp://www.phworld.org/history/attcrash.htmhttp://en.wikipedia.org/wiki/Therac-25http://en.wikipedia.org/wiki/Therac-25http://en.wikipedia.org/wiki/Therac-25http://en.wikipedia.org/wiki/North_American_Aerospace_Defense_Command#False_alarmshttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://en.wikipedia.org/wiki/Software_bughttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://history.nasa.gov/SP-350/ch-11-4.htmlhttp://en.wikipedia.org/wiki/Grace_Hopper

SEI Capability and Maturity Model Test Coverage Criteria, Bug Open/Close Rate Metrics, Pass/Fail Statistics Provide Quantitative Management [Level 4]

Automation is a Step Toward Optimization – Necessary, but Not Sufficient (Metrics for Feedback Process Improvement)

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Ad Hoc, “Code & Fix” – Driven by

Individual Styles, Un-coordinated,

More of an Art than Practice

Clear Phases with Key

Deliverables – Analysis,

Design, Units, Test Plans

E.g. Boehm’s “V” and

Spiral Model, Applied to

All Projects - Repeatable

Entry/Exit Criteria for

Phases, Metrics Drive

Decisions in Process [Gates]

Feedback Used to

Improve Process with

Automation and Innovation

SEI CMM Levels

http://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htm

http://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htmhttp://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htmhttp://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htmhttp://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htmhttp://www.tutorialspoint.com/cmmi/cmmi-maturity-levels.htm

Transformation Systems - Examples Continuous

…

Brightness

and Contrast

Canny Edges

Hough Linear

Hough

Circular

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Learning Objectives

Why is Transformation an Important Architecture and Design Pattern? – Class of Applications that Transform Data Sets

How do We Architect, Design, Code? – OO or Structured Dataflow?

CPU Clocks are Hitting Limits – Use Concurrency

How Much Concurrency is Enough? – Prototype and Measure [Let’s Do that …]

Define High Level and Detailed Requirements

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Activity #1

Demo – Continuous Image Transformation

Requirement #1 – Purpose of Transformation [Enhance,

Segment, Recognize, other?]

Requirement #2 – On-line Real-Time, Off-line

Requirement #3 – Transform Mathematics / Algorithm

Requirement #4 - Thread Grid Sizing? [Inter/Intra Frame]

Requirement #5 – Frame Rate? [24Hz, 30Hz, 60Hz, ?]

Requirement #6 – Resolution? [Fixed, Variable]

…

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Assignment #1

Specify Major Requirements

Test Prototype Reference Code - http://mercury.pr.erau.edu/~siewerts/se300/code/

High-Level Block Diagram – Dataflow, I/O, Processing

Requirements Detail

Prototype Revision and Testing

http://mercury.pr.erau.edu/~siewerts/se300/assignments/

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http://mercury.pr.erau.edu/~siewerts/se300/code/http://mercury.pr.erau.edu/~siewerts/se300/code/http://mercury.pr.erau.edu/~siewerts/se300/assignments/

Let’s Look at Some Code – At Home

Threading and Image Segmentation for Multi-Core

Processing

Example Published in IBM Paper

– Thread, Vector Processing, Optimization

– Grids for Threading, Step One toward Real-Time Processing

Example of Concurrency and Throughput

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https://www.ibm.com/developerworks/industry/library/ind-cloud-e-learning2/index.html

How to Grid?

Conceptual N x M, but Perhaps Just Columns or Rows?

What is Simplest?

Does it Matter at Architecture or Design Level?

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A Couple Examples to Get You Going ... Review, Build, Run

1. simplethread

2. simple-imageproc

3. imageproc-thread

Speed-Up?

– 15.77 sec, 99.8%

– 04.66 sec, 562.6%

4 Hyper-threaded

CPUs

8 VCPUs

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http://mercury.pr.erau.edu/~siewerts/se300/code/simplethread/http://mercury.pr.erau.edu/~siewerts/se300/code/simple-imageproc/http://mercury.pr.erau.edu/~siewerts/se300/code/simple-imageproc/http://mercury.pr.erau.edu/~siewerts/se300/code/simple-imageproc/http://mercury.pr.erau.edu/~siewerts/se300/code/imageproc-thread/http://mercury.pr.erau.edu/~siewerts/se300/code/imageproc-thread/http://mercury.pr.erau.edu/~siewerts/se300/code/imageproc-thread/http://mercury.pr.erau.edu/~siewerts/se300/code/imageproc-thread/http://mercury.pr.erau.edu/~siewerts/se300/code/imageproc-thread/

Assignment #1 – Q&A

Discussion – Status from Individuals or Small Teams

Challenges?

Observations?

Process Issues, Likes, Dislikes? – Waterfall, Waterfall

with Feedback, Evolutionary, Other

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Assessment

Quiz on Pressman Chapters 1 to 3

Foundational Concepts Discussed in Class

2+ Quizzes, I will Likely Drop One of Your Lowest

Scores

The Reading is Important Reinforcement to In-Class

Discussion, At-Home Exercises, and We Won’t Just

Lecture to “Read you the Text”, so Please Read on your

Own and Bring Questions to Class

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