This isn't really a criticism of this article - at first glance it looks well-written and well-informed. The problem I have with articles like this is that it just doesn't fit my own experience of a decade+ worth of application performance work... I worked on lots of projects where something was slow or under-performing, and it was almost never as simple as some loop or generic function. And, if you are performance bound in the way the author states as a hypothesis, my experience is that you have an architecture problem, not just a problem with a single function. Case in point, a few years ago I worked on a project where the original requirements were stated as needing to process maybe 10,000 images a day. In reality, the need was to process something on the order of 10 million images. Two very different needs. So while there are interesting things to be learned from articles like this, they just don't fit my own observations when it comes to what's necessary to boost the real performance of applications in the wild.