The Software Architect Elevator

Chapter 39. Who Likes Standing in Line?

Good Things Don’t Come to Those Who Wait

100% utilization

When in university, we often wonder whether and how what we learn will help us in our future careers and lives. While I am still waiting for the Ackerman function to accelerate my professional advancement (our first semester in computer science blessed us with a lecture on computability), the class on queuing theory was actually helpful: not only can you talk to the people in front of you in the supermarket checkout line about M/M/1 systems and the benefits of single queue, multiple servers systems (which most supermarkets don’t use), but it also gives you an important foundation to reason about economies of speed (Chapter 35).

Looking Between the Activities

When looking to speed things up in enterprises, most people look at how work is done: are all machines and people utilized, and are they working efficiently? Ironically, when looking for speed, you mustn’t look at the activities, but between them. By looking at activities you may find inefficient activity, but between the activities is where you find inactivity, things sitting around and waiting to be worked on.

Inactivity can have a much more detrimental effect on speed than inefficient activity. If a machine is working well and almost 100% utilized but a widget must wait three months to be processed by that machine, you may ...