shine a light on LAMPS

LAMPS 'A four-year 200 person-year effort involving millions of lines
of code, it was evolutionarily delivered in 45 timeboxed iterations
(one month per iteration). This is the earliest project example I found
where the length of iteration was in the range commonly recommended by
today's IID methods...
It is described by the noted 1970s thought leader Harlan Mills in
"Principles of Software Engineering" IBM Systems Journal Vol 19(4)
1980.'

pages 83-84, Craig Larman, "Agile and Iterative Development: A
Manager's
Guide" and similar comments in "Iterative and Incremental Development:
A Brief History" http://www2.umassd.edu/SWPI/xp/articles/r6047.pdf


Happily, the IBM Systems Journal is available online, here's the index
page:
http://domino.research.ibm.com/tchj...xpand=26.4#26.4

Unhappily, all that Harlan Mills writes about LAMPS is:
"LAMPS software was a four-year project of over 200 person-years of
effort, developing over three million and integrating over seven
million words of program and data for eight different processors
distributed between a helicopter and a ship, in 45 incremental
deliveries. Every one of those deliveries was on time and under
budget." p415

Harlan Mills *never* mentions "timeboxed iterations (one month per
iteration)" in the cited article.

Can anyone shine a light on why Mr Larman added this information?
(Maybe Mr Larman had another source which wasn't cited?)

"Isaac Gouy" <igouy@yahoo.com> wrote in message
news:1106868643.035674.9200@c13g2000cwb.googlegroups.com...
> LAMPS 'A four-year 200 person-year effort involving millions of lines
> of code, it was evolutionarily delivered in 45 timeboxed iterations
> (one month per iteration). This is the earliest project example I found
> where the length of iteration was in the range commonly recommended by
> today's IID methods...
> It is described by the noted 1970s thought leader Harlan Mills in
> "Principles of Software Engineering" IBM Systems Journal Vol 19(4)
> 1980.'
>
> pages 83-84, Craig Larman, "Agile and Iterative Development: A
> Manager's
> Guide" and similar comments in "Iterative and Incremental Development:
> A Brief History" http://www2.umassd.edu/SWPI/xp/articles/r6047.pdf
>
>
> Happily, the IBM Systems Journal is available online, here's the index
> page:
> http://domino.research.ibm.com/tchj...xpand=26.4#26.4
>
> Unhappily, all that Harlan Mills writes about LAMPS is:
> "LAMPS software was a four-year project of over 200 person-years of
> effort, developing over three million and integrating over seven
> million words of program and data for eight different processors
> distributed between a helicopter and a ship, in 45 incremental
> deliveries. Every one of those deliveries was on time and under
> budget." p415
>
> Harlan Mills *never* mentions "timeboxed iterations (one month per
> iteration)" in the cited article.
>
> Can anyone shine a light on why Mr Larman added this information?
> (Maybe Mr Larman had another source which wasn't cited?)

Four years is 48 months; i.e. the average iteration is somewhat over
a month. Given that 45 scheduled deliveries in a four year project
at that time is unusual enough to be jaw-dropping astonishing,
I don't find the notion that they were planned as one month
time boxes at all unlikely. On the other hand, I can very easily
see overlapping development of components so that the notion
of time boxes wouldn't apply across the entire project.

Another source would be helpful.

John Roth
>

Isaac Gouy wrote:

> Happily, the IBM Systems Journal is available online, here's the index
> page:
>
http://domino.research.ibm.com/tchj...>
nd=26.4#26.4
>
> Unhappily, all that Harlan Mills writes about LAMPS is:
> "LAMPS software was a four-year project of over 200 person-years of
> effort, developing over three million and integrating over seven
> million words of program and data for eight different processors
> distributed between a helicopter and a ship, in 45 incremental
> deliveries. Every one of those deliveries was on time and under
> budget." p415
>
> Harlan Mills *never* mentions "timeboxed iterations (one month per
> iteration)" in the cited article.

OH MY GAWD, Isaac you're RIGHT!

Strict XP/Scrum/IID etc says we have to get all the iterations EXACTLY THE
SAME LENGTH (or the metrics don't work).

But the LAMPS project could have used UNEQUAL iteration lengths!! They could
have followed calendar months, introducing extra days and such into each
iteration to match the "thirty days has November April June and No Wonder"
fudge factor! They could have simply delivered whenever they finished a
batch of features, and the "45 deliveries" over "four years" could simply be
the total of ALL KINDS of iteration lengths!!!

My FAITH in Larman's book, and in fact all of the incremental and iterative
software engineering movement(s) has been SHAKEN!!!

(Besides, I thought the entire Linux apache MySQL Perl Server architecture
was created over many, many more years, engineers and iterations...)

--
Phlip
http://industrialxp.org/community/b...tUserInterfaces

> Four years is 48 months; i.e. the average iteration is somewhat over
> a month. Given that 45 scheduled deliveries in a four year project
> at that time is unusual enough to be jaw-dropping astonishing,
> I don't find the notion that they were planned as one month
> time boxes at all unlikely. On the other hand, I can very easily
> see overlapping development of components so that the notion
> of time boxes wouldn't apply across the entire project.
>
> Another source would be helpful.

Of course! The 17 incremental deliveries for STS-1 over a 31 month
period became 'timeboxed iterations in the eight-w range", I should
have realized Mr Larman might have made that assumption again.

Overlapping concurrent development, with regular deliveries; or 36
months before the first delivery then drip, drip, drip; or ... ;(or
development in one-month timeboxes).
Yes, a source would be preferable to guesswork.

Isaac,

> Harlan Mills *never* mentions "timeboxed iterations (one month per
> iteration)" in the cited article.
> Can anyone shine a light on why Mr Larman added this information?
> (Maybe Mr Larman had another source which wasn't cited?)

The LAMPS project is apparently discussed (secondary source) in Tom
Gilb's 1988 "Principles of Software Engineering Management", p. 104; I
don't own the book myself, someone who does might be able to check what
language Gilb uses.

Laurent

Isaac,

> Of course! The 17 incremental deliveries for STS-1 over a 31 month
> period became 'timeboxed iterations in the eight-w range", I should
> have realized Mr Larman might have made that assumption again.

I would be prudent with the hypothesis that Larman was careless in
inferring whether a given project was using timeboxed, constant-length
iterations vs. some other model; an earlier paragraph of the "History of
Iterative" article states:

"Yet, some varying and common traits are noted, such as differences in
the lifecycle details. For example, the length of iterations, and
whether or not they were timeboxed."

Of the TRW project, for instance, Larman notes: "The iterations were not
strictly timeboxed, and there was significant up-front specifications
work."

In "Evo: The Evolutionary Programs Managers Handbook", Gilb refers to
the LAMPS project and notes "cycles were about monthly for 4 years".
Maybe that's where Larman got constant length of one month for LAMPS.

Unlike Larman, Gilb is clear on the difference between iterative
*delivery* and iterative *development*, and cites LAMPS as an example of
the former.

Perhaps Larman is deducing "timeboxed" from "Every one of those
deliveries was on time". Isn't that what "timeboxed" means ? :)

Laurent

> The LAMPS project is apparently discussed (secondary source) in Tom
> Gilb's 1988 "Principles of Software Engineering Management", p. 104;

"In IBM Systems Journal (No. 4, 1980) Harlan Mills, IBM's chief
software guru, reports extensive experiences with evolutionary
delivery. His model is closer to what we are recommending in this book,
although it lacks many of the same elements thas SDC lacked. It does
seem to work on the basis of some sort of handover to users.
Here are some quotations which characterize the IBM Federal Systems
Division experience:
'Management has learned to expect on-time, within-budget deliveries.
'LAMPS... a 4-year... 200 person-years' (project was delivered) 'in 45
incremental deliveries. Every one of those deliveries was on time and
under budget.'"

> I would be prudent with the hypothesis that Larman was careless in
> inferring whether a given project was using timeboxed,
> constant-length iterations vs. some other model
-snip-

True, sorry, my frustration is showing.

Figure 7.10 (Principles of Software Engineering Management, p105) on
the page opposite the tiny LAMPS extract, is redrawn from another of
"The management of software engineering" articles Part 5, R.E.Quinnan)
- the figure description begins: "The IBM FSD evolutionary cycle. Every
month the status of the cost and schedule is measured..."


In the original, there's no text with the "Design-to-cost" figure, this
is from the main text:
"Expenditures are not merely projected on a month-by-month basis; they
are related to specific work components and completion dates." p472 IBM
Syst J 19(4) 1980


"Design is an iterative process in which each design level is a
refinement of the previous level. At each stage, design and cost
alternatives are examined. Those that best satisfy the project
objectives are prepared for review and selection by the project
sponsor. If no alternative fits the cost target, several courses of
action are available. The most common one is to go back to the
designers and ask for a less costly, and perhaps less attractive,
design. If the target has been missed by a large amount - and cost is
critical - redesign may not produce an answer. In this case, the
sponsor has to consider giving up some of the planned capability of the
system. Otherwise, he has to recognise that the capability cannot be
acquired without increasing the cost target. The design process is
followed until the program design for a specific software increment has
been completed. From that point, development of each increment can
proceed concurrently with the program design of the others.

When the development and test of an increment is complete, an estimate
to complete the remaining increments is computed. The algorithms used
in this computation should reflect the various actual productivity
rates experienced in developing and testing previous increments." p474
http://www.research.ibm.com/journal.../ibmsj1904G.pdf

Isaac Gouy wrote: 
over 
>
> Of course! The 17 incremental deliveries for STS-1 over a 31 month
> period became 'timeboxed iterations in the eight-w range", I
should
> have realized Mr Larman might have made that assumption again.
>
> Overlapping concurrent development, with regular deliveries; or 36
> months before the first delivery then drip, drip, drip; or ... ;(or
> development in one-month timeboxes).
> Yes, a source would be preferable to guesswork.

To be absolutely clear: I don't know why the text refers to "timeboxed
iterations (one month per iteration)", so all I can do is guesswork.

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Isaac,

You know one thing that keeps bothering me with these flow diagrams
describing project lifecycles - not one of them ever features a terminal
box labeled "Cancel the project".

> When the development and test of an increment is complete, an estimate
> to complete the remaining increments is computed. The algorithms used
> in this computation should reflect the various actual productivity
> rates experienced in developing and testing previous increments." p474
> http://www.research.ibm.com/journal.../ibmsj1904G.pdf

Nothing new under the sun, eh ? :)

Have we shone enough light on LAMPS ?

Laurent