The Efficiency Paradox and How to Save Yourself and the World

QCon London 2025

Session

The Efficiency Paradox and How to Save Yourself and the World

Monday Apr 7 / 05:05PM BST, Mountbatten (6th Fl.)

Abstract

Inefficiency is ruining our planet and our lives. Efficiency is ruining our happiness, and weirdly, it’s also ruining our efficiency. Heeeeelppp!? What’s a techie to do? In this talk, Holly walks through a range of techniques that can be used to find and eliminate software waste and reduce climate impacts. For example, zombie servers and slow code are a big climate problem, but the vrrrooom model gives us double-win hope.

But machine efficiency isn’t much use without human efficiency. The good news is that there isn’t as much of a tradeoff as you might think between these two types of efficiency. Sorting out machine efficiency often helps humans, too. For example, the Quarkus Java framework uses many interesting waste-reduction techniques. These optimizations have the dual benefit of speeding up computers, and also speeding up people.  

So far, so good, but we need to be careful we don’t end up accidentally optimizing the wrong things, and making stuff worse. 100% utilization is not sustainable for either humans, or people. It’s not even very efficient (remember the paradox part?). It turns out, thinking about efficiency needs systems thinking. Holly will draw lessons from performance engineering, mathematics, economics, and psychology to give guidance on how to achieve more by doing less. 

76% senior dev or higher
1:11 speaker ratio
60+ practitioners

QCon London 2025 is a three day conference for senior software engineers, architects and team leads. An international program committee of working engineers selects every session. Patterns and practices, not products and pitches.

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Monday 7 April

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