Establishing Release Quality Levels and Release Acceptance Tests

Establishing Release Quality Levels
and Release Acceptance Tests

Insight Forum
April 21, 2009

© 2009, Enthiosys Inc. All rights reserved. www.enthiosys.com or 650.528.4000
1

About Luke Hohmann

• Founder/CEO of Enthiosys
– Agile Product Management consulting
– Customer needs, roadmaps, business model
– Product management mentoring and training
• Agile product guy
– VP Bus Dev (Aladdin), VP Eng &Product Dev’t
(Aurigin), VP Systems Eng (EDS Fleet Services)
– Board of Agile Alliance
• Author, speaker, blogger
– “Innovation Games”
– “Beyond Software Architecture”
– “Journey of the Software Professional”
– agile PM blog at www.Enthiosys.com
2

Goals

1. Provide a framework for thinking about quality
2. Create better results by building the right quality
3. Practical advice to
help you succeed
What
did I
forget?

3 3

Agenda

• Some discussion – what’s a release? quality?
• The iron triangle or the quality box?
NOT
• Release quality levels
A
• Release acceptance tests TOOLS
TALK

4

Discussions (5 min)

• What’s a release?

• What’s quality?

5

What do we offer? And why?

• We offer things to our market ecosystem
(customers, analysts, etc.) to achieve goals
– A release is offered to generate revenue
– Lo-fi prototypes are offered to improve designs
– Betas are offered to gain pre-release feedback
(and maybe generate revenue…)

• To be offered a thing has to have a “quality” that is
suitable to helping us realize the goal

6

What is Quality?

• “Quality is conformance to user requirements.”
—Phillip Crosby, Quality is Free (1980s)
• “Quality is the absence of defects that would make software
stop completely or produce unacceptable results.”
—Capers Jones, Applied Software Measurement (1991)
• “Quality is achieving excellent levels of fitness for use,
conformance to requirements, reliability, and maintainability.”
—Watts Humphrey, Managing the Software Process
(1980s)
• “Quality is value to some person.”
—Jerry Weinberg, Quality Software Management (1992)

7

Is that enough?

• What about the manner in which we create “the
thing”? What about the code?

• What if the code is just plain ugly?

• And if you’re using an Agile method, what if your
code doesn’t pass the green bar?

8

Quality is a Relationship

• High Performance is High Quality
– to users who notice low performance.
• Elegant Coding is High Quality
– to developers who place high value on the opinions of
their peers.
• Zero Defects is High Quality
– to users who would be disturbed by those defects.
• Lots of Features is High Quality
– to marketers who believe that features sell products.

9
©2008 Information Architects, Inc.

The Dichotomy of Quality

• Intrinsic or Extrinsic?
– Does quality exist in the things we
observe or is it subjective, existing
only in the eye of the observer?

“You take your analytic knife, put the point directly
on the term Quality and just tap, not hard, gently,
and the whole world splits, cleaves, right in two—hip
and square, classic and romantic, technological and
humanistic—and the split is clean.”
—Robert Pirsig
Zen and the Art of Motorcycle Maintenance (1974)
10

Total Quality is therefore…

Extrinsic Quality = Value

Total Quality
Intrinsic Quality = Craftsmanship

11
©2008 Information Architects, Inc., Adapted and Extended

Agenda

• Release acceptance test

12

Should the triangle be a box?

The Traditional Iron Triangle The Quality Box
Value Quality
Scope (Intrinsic quality)
(Extrinsic quality)

Cost Schedule Cost Schedule

13

It is a system

The Traditional Iron Triangle The Quality Box
Value Quality
Scope (Intrinsic quality)
(Extrinsic quality)

Cost Schedule Cost Schedule

14

What can affect the system?

• Flip-chart exercise

15

Choosing to affect the system

The Quality Box Extrinsic Quality
Value Quality • Which features present?
(Extrinsic quality) (Intrinsic quality) • How well do the work?
• How well have they been tested?
• Do you have enough?
• Is this release ready when I need it?

Intrinsic Quality
• Craftsmanship of the code
• Maintainability
Cost Schedule • Level of defects (works as specified)
Let’s hold these as fixed…

16

Agenda

• Release acceptance tests

17

Release quality level

• A predetermined quality level chosen by
product management that sets
expectations regarding the intrinsic and
extrinsic quality of a release.
• Enables organizations to make confident
decisions about their context
• Negotiated with development
18

Example from VeriSign Managed Security Services
Release Level Description

Release Level 5 • All functionality fully certified.
• Near-zero probability of high severity errors and a low probability that medium severity errors.

Release Level 4 • All new and modified functionality fully certified, except where risk is deemed minimal (e.g.
internal facing reports, low probability use cases).
• Features not fully certified documented in the test plan and/or project charter. Strategic
regression testing of existing functionality performed.
• Low probability that high severity errors will be identified in production. Project carries a
moderate probability that medium severity errors.

Release Level 3 • All new and modified functionality at least partially certified.
• Features not fully certified documented in the test plan and/or project charter.
• Partial regression testing performed.
• Moderate probability for high severity errors. Higher probability for medium severity errors.

Release Level 2 • Most new and/or modified functionality partially certified.
• Features not fully certified communicated to stakeholders.
• Partial regression testing performed.
• Higher probability that high and medium severity errors will be identified.

Release Level 1 • New and/or modified features not certified by QA.
• Regression testing may or may not occur.
• Level 1 releases may be available only for demo or controlled access purposes.
• High risk for high severity errors.

19
©2007 VeriSign, Inc. Presented at Agile 2007 conference with Enthiosys
19

Set each scale separately

Intrinsic Quality Extrinsic Quality

5 • Everything certified! 5 • Customers will rave about this!
• Lots of automation!

4 • All new stuff tested by QA 4 • Consistency very high
• Full regression testing • Simple and sophisticated tasks

3 • All new stuff tested by QA 3 • Documented
• Almost full regression testing • Complete for basic tasks

2 • Most new stuff tested by QA 2 • Not documented
• Partial regression tested • Complete for basic tasks

1 • Not tested by QA 1 • Not documented
• Not regression tested • Possibly incomplete

20

Lower bound for
intrinsic quality is very high
• Leading edge enterprises employ technologies that can
approach 99% cumulative defect removal rates.
• The norm for US firms is a cumulative defect removal
rate of 75%.
• A cumulative defect removal rate of 95% on a project
appears to be a nodal point where several other benefits
accrue. For projects of similar size and type, these
projects:
– have the shortest schedules.
– have the lowest quantity of effort in terms of person-months
– have the highest levels of user satisfaction after release
—Capers Jones, Applied Software Measurement (1991)

21

Why is
Intrinsic Quality so Important?
• The Impact of code quality on testing
• Error Location Dynamics
• Error Feedback Ratio
• Technical Debt

22

Impact of Code Quality on Testing

Development: 10 days,
Test time=
4 people, 4 KLOC, 2 days
1 d/KLOC

Development: 10 days, How long to test? Assume Test time=
½ day to find & fix per defect. 30 days
4 people, 4 KLOC,
15 d/KLOC

Outcome: no time to finish testing,
technical debt increases!

23

Error Location Dynamics

64

56
Difficult errors
48 take longer to find:

40 1 hr/d to 50 hr/d
Errors Located
32

24

16

8

0
0 2 4 6 8 10 12

Time

24

Error Feedback Ratio
The time to finish removing errors
The time to finish removing errors
is critically dependent on the error
is critically dependent on the error
feedback ratio. The three simulations
feedback ratio. The three simulations
differ only in their feedback ratios.
differ only in their feedback ratios.
A 20% difference in feedback ratio
A 20% difference in feedback ratio
leads to an 88% difference in
leads to an 88% difference in
completion time, but the next 10%
completion time, but the next 10%
increase leads to aa112% increase.
increase leads to 112% increase.

ERROR FEEDBACK: Errors put into a system when attempting to correct
other faults.

ERROR FEEDBACK RATIO: The number of problems created per fix.
EFR = ERRORS CREATED / ERRORS RESOLVED
25

Technical Debt
Customer • Once on far right of curve,
Responsiveness
all choices are hard
• If nothing is done, it just
Cost of Change (CoC)

Actual gets worse
CoC
• In applications with high
technical debt, estimating
is nearly impossible
Product Technical Debt • Only 3 strategies
Release – Do nothing, it gets worse
Optimal CoC – Replace, high cost/risk
– Incremental refactoring,
1 2 3 4 5 6 7 8 commitment to invest
Years
26

Agenda

• Release acceptance tests

27

Lots of Testing Options!

Customer Usability
Tests Testing
Business Intent
Exploratory
(Fit, Fitnesse)
Run each time a story Testing
scenario is completed Assess each iteration

Programmer Property
Tests Testing
Design Intent Response,
Security
(xUnit) Scaling,…
Run at least once each
development episode Assess each iteration

© From Enthiosys Inc. http://www.testing.com/cgi-bin/blog/2003/08/21#agile-testing-project-1
2009, Brian Marick All rights reserved. www.enthiosys.com or 650.528.4000
28

Release Acceptance Tests

• Tests owned and written by the product
manager / product owner / customer to verify that
a story is complete and correct.
• Should be (mostly) automated (more later)
• Popularized by Agile methods, useful everywhere!

29

Benefits of Acceptance Tests

• Increase team confidence that the system is correct
• Help PMs think through requirements
• Informs developer estimates
• Concrete definition of completion
• Early involvement of QA
• Automated regression testing for free

30

ATs test the users’ experience

• UTs should test application logic in detail
generally in isolation

• ATs should test: but not...
– Interaction & Flow Usability
– Performance Look & Feel
– Error Handling
– Security

31

ATDD Cycle

32

Acceptance Tests are “Quirky”

• Written by PMs/Customers... But executed in code?
– ATs require a customer meta-language generic enough to
capture requirements, abstract enough to be maintainable
– Simple enough to be easily understood
– They are interpreted by various frameworks
– Requires external systems and “spike” development
• Automation tools dictate form/format of tests
– http://www.fitnesse.org/
– http://seleniumhq.org/
– http://robotframework.org
33

Fitnesse Structure

34

Fitnesse test example

Each row is one test

Fitnesse supports many
different testing table
styles that can be
organized into test suites.

35

Writing good acceptance tests

• Tell a story of accomplishing a goal
– Goal  test title
– Activities  rows in your test suite
• Expect them to be stable, even if the underlying
system is going through a lot of change
• Don’t reference domain objects

36

Consider “Given-When-Then”

• Given some context
When something happens
Then some behavior

• Given an innovation games planner with a
scheduled party
When they cancel the party
Then send a cancellation email to the players
and the facilitator, a cancellation confirmation
to the planner, and ensure that the game play
URL points to the “cancelled party” page

37

Overcoming common challenges

• You don’t have to automate everything
• Get started, but don’t expect quick turns
• Help your product managers by writing a few
• Make AT writing a natural part of the conversation

38

Thank You !!!

Luke Hohmann
Founder & CEO
Enthiosys, Inc.
615 National Ave., Ste 220
Mountain View, CA 94043
cell: (408) 529-0319
www.enthiosys.com
lhohmann@enthiosys.com

Innovation Through Understanding®
39

Establishing Release Quality Levels and Release Acceptance Tests

Recommandé

Recommandé

Contenu connexe

En vedette

En vedette (9)

Similaire à Establishing Release Quality Levels and Release Acceptance Tests

Similaire à Establishing Release Quality Levels and Release Acceptance Tests (20)

Plus de Luke Hohmann

Plus de Luke Hohmann (20)

Dernier

Dernier (20)

Establishing Release Quality Levels and Release Acceptance Tests

Notes de l'éditeur