Process Improvement

It is not necessary to change. Survival is not mandatory.

» W. Edwards Deming

Both change and stability are fundamental to process improvement.

» Dennis Ahern

Models

• Models provide a common set of process requirements that capture the best practices and knowledge in a format that can be used to guide priorities.

» CMMI Distilled, Ahern, Clouse, Turner, p5.

Basic Model of Improvement

• Observe some difficulty

• Collect some data

• Identify the root causes (hypothesis)

• Develop reasonable solutions (test)

• Plan and implement the changes

Process Improvement Doesn’t Just Happen

• many models and buzzwords – SEI– ISO 9000– CQI– test process improvement– PSP– CMM– Plan-Do-Check-Act – QIP– …

Emphasis

• high-quality software

• finite amount of resources

• cost-effective manner

Two Observables

• Cost: – Main cost in software is time. (Why?)

• Quality: – correctness– reliability– robustness– user friendliness– verifiability– maintainability– safety

Why is Process Improvement Difficult?

• Software development is:– Evolutionary and experimental– Not production– Human based

• Software is variable:– Processes– Goals– Content

• We lack models:– Needed to to reason about the process and the product

Capability Maturity Model (CMM) for Software

Capability Maturity Model (CMM) for Software

• Process Capability– ability of a process to produce planned results

• Software Engineering Institute (SEI)– Carnegie Mellon

• 5 Levels

• Certification based on audits

5 Stages of CMM for Software

• Level 1: Initial

• Level 2: Repeatable

• Level 3: Defined

• Level 4: Managed

• Level 5: Optimizing

Initial

RepeatableDefined

ManagedOptimizing

Initial• Ad hoc• No process in place

RepeatableAchieved a stable process with a repeatable level of statistical control

DefinedAchieved foundation for major and continuing progress

Managed Substantial quality improvements• Comprehensive measurements

OptimizingMajor improvementsin quality and quantity

Basic

management

control

Process

definition

Process

management

Proce

ss

contro

lSEI Capability Maturity Model

Level Focus

Initial Heroics

Repeatable Basic project management

Defined Process standardization

Managed Quantitative management

Optimizing Continuous process Improvement

CMM Maturity Level 1: Initial

Characteristics

• No sound SE management principles in place

• Ad hoc practices

• May be successful because of competent manager and team

• Activities are not preplanned, but response to crisis

• Unpredictable process

• Cannot predict time and cost of development

To get to next level

• Initiate project management

Elements of Basic Project Management

• Software Configuration Management• Software Quality Assurance• Software Acquisition Management• Software Project Control• Software Project Planning• Software Requirements Management

CMM Maturity Level 2: Repeatable

Characteristics

• Basic SE management practices in place

• Planning and management are based on experience with similar products (repeatable)

• Track costs and schedules

• Identify problems as arise and take immediate corrective action

To get to next level

• Standardize Processes

Process Standardization• Peer Reviews• Project Interface Coordination• Software Product Engineering

– methods and technologies– software development process architecture

• Integrated Software Management• Organization-level Awareness

– Organization Training Program– Organization Process Definition– Organization Process Focus

CMM Maturity Level 3: Defined

Characteristics

• Process for development fully documented

• Reviews used to achieve software quality

• Introduce CASE Tools

To get to next level

• Quantitative Management

Quantitative Management

• Statistical process management – quantify quality and cost parameters

• Process database to maintain process data

• Assess relative quality of each product

CMM Maturity Level 4: Managed

Characteristics

• Organization sets quality and productivity goals for each project

• Continually measure

• Statistical quality control in place

To get to next level

• Support automatic gathering of process data

• Use data to analyze and modify the process

• Defect Prevention

CMM Maturity Level 5: Optimizing

Characteristics

• Statistical quality and process control techniques are used and guide the organization

• Process has positive feedback loop

To maintain level

• Continue improvement and optimization of the process

Other Improvement Process Models-1

Plan-Do-Check-Act (Deming) (Improving single process within an organization)

• Plan. Develop plan for effective improvement• Do. The development organization carries out the

plan• Check. After process termination, observe the

effects of the change or test• Act. Study the results and document the lessons

learned. Emphasis on– understanding the principles of the process, – predicting product’s quality– suggest further improvement

Other Improvement Process Models-2

Quality Improvement Paradigm (NASA Goddard) (Systematic software development and SE technology validation )• Characterize project using models and baselines • Set quantifiable improvement goals on basis of relevance to

organizing successful project and organization performance improvement

• Execute the plan to develop products and provide feedback• Analyze the collected data and information gathered and evaluate

the current practices, determine problems, record findings, and make recommendations for improvement

• Package the experience in the form of new, updated or refined models. Store them in an experience base so it is available for future projects.

Process Improvement Framework Quagmire

CMMI: CMM Integrated

Reduce Cost:– eliminate inconsistencies between processes– Reduce duplication– Provide common terminology and style– Increase clarity

CMMI Principles• Maintain executive support

– Strong consistent support is crucial

• Pick your targets carefully– Don’t underestimate effort

• Leverage best practices– “Steal with pride”

• Align process improvement with your business objectives– Improve your business

The Model• Required: Statement of Goals

– a desirable end state; succinct– Example: Requirements are managed and inconsistencies with

plans and products are identified

• Expected: Statement of a Practice– the expected means of achieving a goal– every practice maps to exactly one goal– Example: Develop an understanding with the requirements

providers on the meaning of the requirements

• Informative: 10 types of information components identified (e.g. purpose, reference, typical work products)

Goals of the capability levels

Level Goal

CL 0 No goal

CL 1 The process supports achievement of specific goals of the process area by transforming identifiable inputs to identifiable outputs

CL 2 The process is institutionalized as a managed process

CL 3 The process is institutionalized as a defined process

CL 4 The process is institutionalized as a quantitatively managed process

CL 5 The process is institutionalized as an optimizing process

Level 3

• Defined: For each process area considered, each project in the organization will have a managed process (created under Level 2) that is tailored using standard guidelines.

4 process categories

• Process Management

• Project Management

• Engineering

• Support

4 process areas

• Process Management– Process Definition– Training

• Project Management

• Engineering

• Support

4 process areas

• Process Management

• Project Management– Project Planning– Monitoring and Control– Risk Management

• Engineering

• Support

4 process areas

• Process Management

• Project Management

• Engineering– Requirements Development and Management– V&V– Product Integration

• Support

4 process areas

• Process Management

• Project Management

• Engineering

• Support– Configuration Management– Measurement and Analysis– Decision Analysis and Resolution

Summary: Process improvement

• May not be necessary for a given project

• May be neglected by some companies

• May be necessary for survival of

– companies

– employees