Slashdot Mirror


"Mythical Man-Month" Supposedly Busted By MIT Startup

An anonymous reader writes "We all know about the Mythical Man-Month, the argument that adding more programmers to a software project just makes it later and later. A Linux startup out of MIT claims to have busted the myth, using an MIT holiday month to hire 20 college student interns to get all their work done and quadrupling its productivity."

19 of 231 comments (clear)

  1. !MMM by seanadams.com · · Score: 5, Insightful
    Aside from being in the same room, these programmers were barely working together. This was NOT an attempt to accelerate a single, large, overdue project (the Mythical Man Month problem) - and they explicitly say so! I wonder if the submitter even read the book, or just heard the title somewhere and thought it was a catchy buzz phrase.

    Give interns loosely-coupled projects. Our internship program would never have worked if we had assigned a dozen new people to hack on our kernel code--the training time and communication costs that drive Brooks' Law would have swallowed their efforts whole. Fortunately, like any growing business, we had a constellation of projects that lie around the edges of our core technology: infrastructure upgrades, additional layers of QA, business analytics, and new features in the management side of our product. Few of these had elaborate technical interfaces with any of our existing software, so our interns were able to become productive with minimal ramp-up and rely on relatively little communication to get their projects done.

    In other words: they had an "embarrassingly parallel" problem and did the obviously right thing.

    1. Re:!MMM by blahplusplus · · Score: 3, Insightful

      "In other words: they had an "embarrassingly parallel" problem and did the obviously right thing."

      Exaclty I'd like to see the poster try to keep adding people to a game project. I've seen so many abortions from the game industry lately it's disturbing.

    2. Re:!MMM by sjames · · Score: 4, Insightful

      Exactly. They didn't add people to a late project, they got more people and put them on un-manned projects to get them going. That's quite a different matter and not what Brooks was talking about. And yes, they did the right thing.

    3. Re:!MMM by pthisis · · Score: 5, Insightful

      Even there, they didn't come anywhere close to disproving Brooks' theory.

      If you throw 20 programmers at a task, the square root of 20 is 4.472+. They got a factor of 4 (at best) improvement. To even begin to claim that productivity improves with the number of programmers (modulo a constant), they'd need to beat that square root.

      They failed. The numbers they're quoting are certainly inconclusive, but in a vacuum they support a sub-linear improvement (the Brooks hypothesis), they don't refute it.

      Certainly there could be a very small constant where these results are inline with a non-Brooksian conclusion, but in a vacuum they're more likely in line with a Brooksian hypothesis than any theory of linear scaling.

      --
      rage, rage against the dying of the light
    4. Re:!MMM by turbidostato · · Score: 5, Insightful

      "Not exactly a representative sample."

      And not a respresentative case till some time passes on. Right now they had a lot of youngsters hacking a lot of separated (micro)projects. Let's see in a few months if this hackaton doesn't become itself a maintenance nightmare, once bugs and design flaws arise.

    5. Re:!MMM by Calinous · · Score: 4, Insightful

      Even as a paying student, it's hard to get to MIT - so they're not nubs like every other CS student in the world. Or if they're nubs, they are the best nubs around (I'm not talking about average, but about the 20 or so people that could be attracted into such a project)

    6. Re:!MMM by tomhuxley · · Score: 4, Insightful

      Computer Science != Software Development

      They may be smart, they may even be brilliant, but computer science at elite institutions has frak-all to do with software development. At best, they will be good newbs, at worst, entitled newbs who are convinced they know it all.

  2. The MM-M is more what you'd call a guideline by ClosedSource · · Score: 4, Insightful

    than an actual rule.

    1. Re:The MM-M is more what you'd call a guideline by Opportunist · · Score: 5, Insightful

      Someone hand that guy a modpoint or two, because adding manpower to a late project can have beneficial effects. If, and only if, it is done sensibly.

      Hire someone who makes sure the programmers have all the pizza and egg rolls they need so they ain't going to be distracted by having to call the pizza place for one. You all know how much time is killed with you get interrupted by something important. Like, say, a rumbling stomach. It takes ages to get back into the code afterwards.

      But more sensibly, fire all the paper pushers and hire project managers worth their salt. And I don't mean "idiots that can set arbitrary milestones". We got plenty of those. A good project manager makes or breaks the project. What I need from a project manager is:

      1) Making sure I have the hardware and software I need. Not "the company thinks I need". The ones I need.
      2) Making sure external sources keep their deadlines or route around those bottlenecks. Know what makes most of my software late? That I finish my modules only to hear "uh... testing can't commence, we're waiting on something from X." A good PM knows that BEFORE it happens and tells you to drop that module and work on this one instead, because the guys at Y are done and we could start testing that part instead.
      3) Most important: SHIELD ME FROM POINTLESS MEETINGS and go there for me. And there, his answers are "no". "Can't do that". And "has to be done on your end". I.e. the crap I usually get to hear in those meetings.

      If necessary, hire more PMs. Not more programmers.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  3. They didn't add to a late project by MMORG · · Score: 4, Insightful

    They didn't add programmers to a late project, they added programmers to a bunch of small, self-contained projects that hadn't been started yet. That's a very different thing.

    The point of Fred Brook's argument is that if you take a project that's already late, that means it already has systemic problems of one type or another (or likely, several types at once). Adding bodies without solving the systemic problems just makes those problems grow, not go away. That's not the situation this company had and that's not what they did. Saying they "busted the mythical man-month" is just trolling.

  4. Agreed by golodh · · Score: 5, Insightful
    You hit the nail on the head. The interns were put on separate problems so there was no need for much communication.

    In addition, the article notes that the company was "a bit spoiled" by being in a position to hire from a large pool of MIT students, many of whom they knew personally. I like the subtle understatement here.

    Not only did they put the target practically in front of the gun (by having an embarrassingly parallel problem), they also employed an embarrassingly high-calibre gun (i.e. hand-picked MIT students). Scoring has therefore been high. Surprise!

    This experiment didn't do anything at all to bust the mythical man-month. Who came up with that title anyway? Must have been some slashdot editor ...

    1. Re:Agreed by mwvdlee · · Score: 3, Insightful

      TMMM is about people actually having to communicate. The situation described here put everybody in the same room due to there not being enough rooms. Given the task, they might as well all had separate office buildings.

      I've worked on in companies with well over thousand IT employees. Those companies didn't have a problem with TMMM either. That's because those thousand people were working on a hundred different projects. This situation is pretty much the same but at a far smaller scale.

      p.s. When an article mentions the product they are making is "supposed to be technically impossible", the rest of the article probably isn't based on reality either.

      This has nothing to do with TMMM, but with them bragging about how they hired a shitload of MIT students and assign each his/her own, separate projects; something any half-decent project manager should be able to pull off. (And this is a guy speaking with a very low esteem of project managers in general).

      --
      Slashdot social media options: AIM, ICQ, Yahoo, Jabber and Mobile Text. Why no MySpace?
  5. 10 years ago by fermion · · Score: 5, Insightful
    Ten years ago the NASDAQ reached 5132, no long after it lost more than half the value. The reason was that people believed the rules no longer applied. For some reason, conservation of energy, momentum, mass, were considered to be obsolete antiquated concepts. Sometimes it takes a smack in the ass to get people back to reality.

    The real issue here, and one that is not addressed, is the quality of code. What the MMM addressed, IMHO, was adding developers to a project with defined metrics and ending up with code that met those metrics and integrated well with a larger code base. The reason that adding people did not work was the overhead needed to communicate between the develpers, which is 2^n proposition

    As such, until the code is proven in service one cannot really say if the experiment worked. If the code is just going to have to be re-factored, or interfaces rewritten, then nothing was done other spending money to achieve a minimal product to meet a deadline. This is important, but does not prove or disprove anything.

    --
    "She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
  6. Don't forget by meerling · · Score: 3, Insightful

    all projects have a point of diminishing returns.
    The key to limiting, or exasperating this problem is good or bad project management.
    Of course, if the 'project' is a large series of little projects that don't have dependency on each other, you can greatly increase personnel easily, such as the people in this argument.
    They didn't really bust the myth, rather they used a situation where they didn't exceed the number of optimal personnel.

  7. Re:Disappointing by Wayne247 · · Score: 5, Insightful

    Not as old as you (in terms of Slashdot readership), but I've been here quite some time as well.

    I think that, as readers left this site, editors slashed into the content quality and try the quantity approach. I used to be able to read the site daily and have time to post replies here and there. Now, I have it set in an RSS reader because the volume is much larger to the point that if I miss a day, 20 to 30 stories fly by.

    It's not that there are more things to report now than 10 years ago, it's all these crappy filler stories, blog posts about nothing interesting, jokes and whatnot that make this site less and less relevant.

    Additionally, while Slashdot used to be where the breaking news was happening, I can now find interesting and important stories up to THREE days later on this site than on digg, for example.

    Me and some other people have submitted, days ago, important stories (in our opinion) about a FOSS company that is suing the Quebec government for the right to bid on contracts that went directly to Microsoft. This is being heard by the supreme court right now. The supreme court! And it's not even making slashdot!

    It's not too late, but the editors really have to try and voluntarily lose a few percent point of page views in order to bring back quality and, more importantly, fellowship of readers.

  8. Niney McNine Nine by morty_vikka · · Score: 3, Insightful

    Maybe it's 98.01% (0.99 squared!).

    Game devs FTW!

  9. Re:This is MIT, remember by Opportunist · · Score: 4, Insightful

    No. No! I need a project manager! And I pride myself with being a fairly good programmer. And even the guys at MIT can benefit from one.

    But I, like every programmer, need a good project manager. One that helps me instead of standing in my way. I don't need someone who checks my "progress" on some arbitrary measure that has nothing in common with the project at hand and peppers my calender with meaningless milestones. I also don't need someone to tell me how to write my code. I need a project manager that understands what he and I are trying to do together: Make a project work out. My job is to create it. His job is to make that possible to me.

    And for that I need a project manager that deals with what I tend to call the "unpleasantries" of projects. In other words, clients, management, in a nutshell: PEOPLE. People make a project late. Especially when they start to meddle with it for some reason. The perfect project manager would lay down the project together with the client, do all the yucky legal stuff around it, give me the specs (not "and here kinda-sorta like $other_program", I mean specs you can work with), then keeps customer, management and all the other unnecessary evils of a project busy while I do my job so I don't get pestered. By meetings. And dumb questions.

    I once actually had a PM like that. And it was a dream. We (him, me and a few other very motivated and talented people) created projects in record time. It was the best year of my life!

    The company did what it does in such cases: They promoted him away from the position he was born for.

    --
    We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  10. Re:Disappointing by scumm · · Score: 5, Insightful

    If you think stories shows up on Digg before /., you should check out Reddit (especially the various tech subreddits). That's where you find the stories 4 days before they show up on Digg.

    Nowadays, I mostly come to /. for the discussions. I will admit that the quality of discourse might have sagged a bit since its heyday, but on a whole I still find genuinely stimulating articles and commentary often enough to be a regular reader after all these years.

  11. Relating to Open Source? by jonaskoelker · · Score: 3, Insightful

    Let me see if I get this right:

    Brooks is saying that you should let everybody look at source code, due do Linus' Law (bug shallowness goes to 100% for eyeballs going to 6e9).

    Parnas is saying that you should encapsulate things behind loosely coupled interfaces.

    And you're saying "if everyone has to know what everyone else is working on [...]"

    And then I'm saying there's a difference between having to know the innards of a module, and being allowed to know said innards.

    I also think being allowed to know---without having to---is what makes open source software what it is.