The Project Manager's Orchestra Problem
Description
The image is a close-up photograph of a printed math or logic problem, labeled as question number 5. The text inside a rounded rectangle reads: 'An orchestra of 120 players takes 40 minutes to play Beethoven's 9th Symphony. How long would it take for 60 players to play the symphony? Let P be number of players and T the time playing.' This is a classic trick question designed to bait the reader into a simple mathematical calculation (halving the players = doubling the time), while the logical answer is that the duration of the symphony remains the same regardless of the number of performers. For senior software engineers, this is a perfect and succinct analogy for Brooks's Law and the 'Mythical Man-Month.' It humorously illustrates the fallacy that development tasks are always parallelizable, mocking the non-technical management perspective that one can simply add or remove developers to proportionally affect a project's timeline, ignoring dependencies, communication overhead, and the inherent sequential nature of much of the work
Comments
25Comment deleted
A project manager tried this logic on me. I asked him if nine women could have a baby in one month. The baby is now our new legacy system
Beethoven’s Ninth still ends at 40 minutes; halving the orchestra just demonstrates to management that Amdahl’s law comes with violas instead of mutexes
Just tried explaining to our new VP why we can't deliver the project twice as fast with double the developers. Should have just shown them this orchestra problem and watched them try to calculate how long it takes 240 musicians to play the same symphony in 20 minutes
This is basically the musical equivalent of 'Nine women can't make a baby in one month' - a perfect analog to Brooks's Law. The problem assumes perfect parallelization with linear scaling, completely ignoring that some tasks have inherent sequential dependencies and coordination overhead. Just like you can't halve your sprint time by doubling your team size, you can't speed up a symphony by reducing the orchestra. The symphony's duration is architecturally fixed by the composition itself, much like how certain algorithms have irreducible time complexity regardless of how many cores you throw at them. This math problem inadvertently teaches us more about the fallacy of naive resource scaling than it does about proportional relationships
120 cores: 40s runtime. 60 cores: 40s. Amdahl's Law auditions for the orchestra
Still 40 minutes - you can’t shard a symphony. Amdahl nods; Brooks mutters, "with onboarding, call it 45."
You can’t multithread a symphony; it’s all latency and zero parallelizable fraction - Amdahl nods, Brooks smirks
those damn project managers and their unrealistic expectations Comment deleted
from entrance test for effective manager position? Comment deleted
A woman needs 9 months to birth a child. How many months would it take to birth a child if 5 women got pregnant at the same time? Comment deleted
From same man or from different? Comment deleted
Same man Comment deleted
geo distributed or single dc? Comment deleted
After nine months you’ll get five babies, so the average birthing speed is 5/9 = 0.56 babies per month Compared to one woman — GREAT SUCCESS Comment deleted
yes. with only one woman we have 0.11 babies per month, thus to increase our monthy output, we’ll have to impregnate more women. easy Comment deleted
obviously this would take 80 minutes instead. ez. gimme an offer Comment deleted
Ебать клоун(such a good man) Comment deleted
It’s me understanding asynchronous programming: Comment deleted
(60×40)÷ 120 Comment deleted
I can't tell if you're joking or not Comment deleted
Still 40 Comment deleted
about tree fiddy Comment deleted
Isn't "Tests for PM" name of the book Comment deleted
That’s not how any of this works Comment deleted
😂😂 Comment deleted