The site reliability engineering (SRE) community has tended to view reliability as a mechanical problem. So we have been meticulously counting “nines,” working on the failover groups, and making sure our autoscalers have all the least settings they need. But something appears to be metamorphosing threateningly: people are becoming increasingly lost in high-availability metrics like 99.99%, which seemingly mask an infrastructure that would melt like butter if not for humans stepping in manually.
We have reached the maximum level of complexity. Modern cloud-native ecosystems, including microservices, temporary Kubernetes pods, and distributed service meshes, are experiencing an exponential growth in the amount of traffic they handle. While the infrastructure continues to scale up and down at will, our human cognitive bandwidth, as defined by Miller’s Law, simply cannot keep up. We are trying to manage state spaces that approach infinity with something as minimalist as biological bandwidth.