Loading ...
Sorry, an error occurred while loading the content.

how do I find bottlenecks?

Expand Messages
  • David Carlton
    Recently, there s been a Google-related discussion going on in the XP mailing list; that reminded me of something Mary said in one of her talks at Agile 2006.
    Message 1 of 47 , Oct 4, 2006
      Recently, there's been a Google-related discussion going on in the XP
      mailing list; that reminded me of something Mary said in one of her
      talks at Agile 2006. Namely: optimizing locally is not only not
      useful, it can be actively harmful. In that context, she suggested
      that Google's policy of letting people spend 20% of their time
      pursuing pet projects actually helps their productivity.

      I'm a manager of a software team; I'm trying to figure out what, if
      any, relevance this has to us. The flip side to Mary's claim is that
      I doubt that the our extended group (us plus all the other teams
      working on the same product) would have a productivity increase if
      they let every single person spend 20% of their time working on pet
      projects. Maybe it would - people would be more energized, and it
      would increase the number of new product ideas floating through the
      air - but, strictly from a queuing theory point of view, I'm a little
      dubious. Instead (I'm taking this from Theory of Constraints), there
      are likely to be bottlenecks in our system that are determining the
      extended group's productivity level; if my team is a bottleneck, then
      we shouldn't lightly give up on-task time.

      So: what do I do to determine if we're a bottleneck?

      (Maybe this is explained in the new book; it's next in my to-read

      Thinking about this, one interesting aspect of XP is that it broadens
      potential bottlenecks, eliminating many traditional ones: bottlenecks
      happen when there's a scarce resource in high demand, but XP's
      knowledge sharing means that individual knowledge is much less likely
      to be a scarce resource. So either the team as a whole isn't a
      bottleneck, or everybody on the team is part of a bottleneck! And
      then a further advantage is that, because of the relatively
      transparency of the value stream map in an XP context, it's probably
      easier to figure out where the bottlenecks are.

      Unfortunately, this transparency is an area where my team (and
      surrounding groups) isn't doing so well: our Customer interaction
      isn't as good as I'd like, and we don't yet have frequent real
      (non-internal) releases. Perhaps as a result, my vision is a bit
      muddled: it seems very useful to figure out where the bottlenecks are
      in the process, but I'm having a hard time figuring that out.

      I guess one traditional answer is "look where work is piling up". On
      the one hand, there's no shortage of requests for us to do stuff, so
      you could say that work is piling up before us. But if there are
      further bottlenecks downstream from us, then that's kind of
      irrelevant; I'm having a hard time seeing whether or not that is the

      David Carlton
    • David Carlton
      ... Some reactions: * Yes, it is worrying: I am worried! * We have a few kinds of quality problems. I think we re getting better on outright bugs, though
      Message 47 of 47 , Oct 9, 2006
        On Mon, 09 Oct 2006 09:41:26 +0100, allan kelly <allan@...> said:

        > David Carlton wrote:
        >> We have had (monthly) regular internal releases in the past. We've
        >> had two problems with those, though:
        >> * They're not real releases: nobody in the outside world is keeping us
        >> honest as to their quality. We try to do a good job of keeping
        >> ourselves honest, but an internal release (or even one for partners)
        >> just isn't the same as an external release.

        > I find this worrying. It sounds like people only take quality
        > seriously when a customer is in sight. So, for the first 11 months
        > of a 12 month project quality can take a holiday.

        Some reactions:

        * Yes, it is worrying: I am worried!

        * We have a few kinds of quality problems. I think we're getting
        better on outright bugs, though there's room to go there.
        Specification mismatches seem to be a harder problem to solve.

        * I don't think I'm unique in feeling that internal releases are
        different from external releases. It's the same sort of reasoning
        that recommends that, in XP speak, your Customer be an actual
        customer, not a customer representative. Or that your daily
        deployments (if you're that far) actually deploy, they're not just
        builds that could be deployed. There's a reason why the value
        stream map ends when the customer actually gets the value, after
        all. :-)

        >> * They're sometimes not fast enough - if we learn now that a big
        >> potential customer wants to start a trial in three weeks, and new
        >> feature X is necessary for the trial, then sticking to a monthly
        >> heartbeat isn't going to do us much good.

        > There are few ways to tackle this.

        > Firstly, this seems to contradict your point above. Surely you want
        > to stay as close to release quality at all times so you can just
        > take what your working on, add feature X and ship it over? Provided
        > your internal releases were good quality this wouldn't be a problem.

        And, indeed, our internal releases are good enough quality that this
        isn't a problem: we have successfully created trial releases in short
        order. All I'm saying is that it means that we're not on a regular
        monthly heartbeat.

        > Second consider what you call your releases. Say your internal
        > releases were called Beta, and you had 4 iterations to each release.
        > Then, again assuming each iteration completed with high quality, the
        > software at the end of each iteration could be called an Alpha.

        > Provided you set expectations with your trial customer they should
        > be happy to work with a Beta or an Alpha. Trials don't need full
        > releases, make it clear to the customer that you can have an Alpha
        > with the feature available for the trial, and say that by the time
        > the trial is finished you will have a release version available.

        That's a good idea - I'll think about that.

        > I suspect, from what you say and my own experience, that when your
        > customer staff come back with a request you drop your current plans,
        > work out how to handle their request, do it, ship something of
        > dubious quality and then try to work out were you are.

        I don't think this is entirely true. I don't think our quality is as
        bad as you're getting a picture of. We do reprioritize work pretty
        often; I guess it's not clear to me that this is inherently a problem.
        (Isn't our ability to do that supposed to be one of the advantages of
        agile approaches?)

        What is bad is if either our interim work is of low quality or if we
        implement something that ends up ultimately not to be useful. We're
        working to avoid the former. I don't really understand how to avoid
        the latter; I wish I did.

        > Consequently, you are thrashing, changing direction and prioritise a
        > lot. (This is also a worry for product strategy if you are driven
        > by ad hoc customer requests. Do your product managers really know
        > what should be in the product?)

        In all honesty, I don't think anybody in the world knows what should
        be in this product. (And if that worries you, well, it worries me
        too.) We're trying to provide new capabilities in an existing space;
        we have a compelling dream for the new capabilities, but nobody really
        understands how the details will play out. And our product will be
        part of a quite complex ecosystem: we need to work with others to
        bring the new capabilities to fruition. At the same time, to displace
        existing deployments, we have to be able to integrate with systems
        that are already in place. And there is a woeful lack of
        standardization, which means that, if we want to target five different
        deployments, we probably have to do five different integrations.

        It's taken us a while to find a good strategy for this. Our current
        favorite one is to partner with systems integrators; I think that will
        help a lot, because it will let us sell basically the same system to
        multiple individual deployments.

        > Most likely your customers really don't want it tomorrow.

        Yes, that is true.

        David Carlton
      Your message has been successfully submitted and would be delivered to recipients shortly.