Architected Agile Solutions for Software-Reliant Systems

Boehm, Barry & Lane, Jo & Supannika, & Turner, Richard. (2010). Architected Agile Solutions for Software-Reliant Systems. INCOSE International Symposium. 20. 10.1007/978-3-642-12575-1_8.

How Much Architecting is Enough?

https://gyazo.com/59270c68a9209b5ce7d26e4efe020777

left-most plan

Red line is the percentage of time spent on preliminary design

Black dotted line is the percentage of time spent redoing

Green is the sum of

The three lines correspond to the number of lines of code

Preliminary design is not necessary for 10,000 lines.

At around 10 million lines, the time lost by redoing can be as much as 91%.

Therefore, it is reasonable to spend 40% of the time on preliminary design to lower the risk of redoing the project.

chart on the right

black line

Average cost for a 100,000 line project

The thin one corresponds to the red line in the left figure, and the two thick ones to the green and black.

Redo cost, design cost, total cost

red line

When design costs increase by 50% due to high specification variability.

Increased design costs

→Sweet spot moves to the left.

= less pre-design would be appropriate.

With a 50% increase in cost, the sweet spot moves from 20% to 10% (actually 15% because of the 50% increase).

green line

50% additional cost when problems occur due to lack of prior design

Higher redo costs

→Sweet spot moves to the right.

= Better to design more in advance.

Sweet spot moves to 30%.

However, about 5-10% of the area above and below is almost flat, so it is more of a "region" than a "spot".

Too few and the risk skyrockets when you come to the edge of the region.

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