A lot of people are pointing out that BigO is a purely theoretical, mathematical model that should be understood and used properly without regard to silly details like physics.
That is theoretically correct. But, the difference between theory and practice is that in practice there exists a large percentage of programmers writing code for the real world without understanding and using BigO properly. Their mental model of performance begins and ends with BigO. As far as they are aware, its model is reality.
Source: I've been giving a large number of programmer job interviews lately. It's a rare day when I encounter an engineer (even a senior one) who is aware of any of the issues brought up in this series. And, I work in games!
That is theoretically correct. But, the difference between theory and practice is that in practice there exists a large percentage of programmers writing code for the real world without understanding and using BigO properly. Their mental model of performance begins and ends with BigO. As far as they are aware, its model is reality.
Source: I've been giving a large number of programmer job interviews lately. It's a rare day when I encounter an engineer (even a senior one) who is aware of any of the issues brought up in this series. And, I work in games!