Kubernetes liveness and readiness probes are mechanisms to improve service reliability and availability. For example, if a container is unresponsive, restarting the container can make the application more available, despite the defect. I have written two articles on how these mechanisms, designed to improve system reliability and availability, can make…
Previously, I wrote an essay describing how Kubernetes liveness and readiness probes can unintentionally reduce service availability, or result in prolonged outages. In the conclusion of that essay, I highlighted Lorin's Conjecture: Once a system reaches a certain level of reliability, most major incidents will involve: A manual intervention that…
This article expands on a keynote that I gave at Reactive Summit 2018. I also discussed these topics on the Real-World Architecture Panel at QCon San Francisco 2018. An operational technology combines hardware and software to monitor and/or control the physical state of a system. Examples include systems used…
Kubernetes liveness and readiness probes can be used to make a service more robust and more resilient, by reducing operational issues and improving the quality of service. However, if these probes are not implemented carefully, they can severely degrade the overall operation of a service, to a point where you…
Services that incorporate streaming workloads often need to perform asynchronous requests to other services, or execute long-running, asynchronous operations. Examples include, inserting time-series data into a database, retrieving metadata for data enrichment, and executing complex business-workflows. Executing asynchronous operations in a streaming context, while maintaining backpressure in the stream, is…
When I was in elementary and secondary school, I did not enjoy reading or writing. Both were a chore. This probably had a lot to do with the fact that the rote learning and clerical curriculum that is core to modern, institutional education, was just not right for me. I…
You have probably had the experience of working tirelessly on a challenging, high-profile, business-critical project, for a significant period of time, chasing the satisfaction of completing the project successfully, only to have it be suddenly finished, completed with very little fanfare, or the gratifying catharsis that you were anticipating. You…
I have never had an internship. In fact, while I was an undergraduate in university, I never even had a summer job related to engineering or software development. I worked at a living-history museum for three summers, giving guided tours, performing artillery demonstrations, and playing bagpipes all day. It was…
I expand on these concepts in my Scale by the Bay presentation. In an earlier article, I detailed a number of techniques that can be used to maximize the throughput for individual Akka Streams. In a subsequent article, I also explored how an Akka Stream can be internally partitioned, in…
I expand on these concepts in my Scale by the Bay presentation. In an earlier article, I detailed a number of techniques that can be used to maximize the throughput for Akka Streams. The article focused on improving the throughput of individual streams and the techniques mainly involved, but were…
This three-part series expands on a talk that I gave at a conference focused on time-series data in 2018. This three-part series is focused on the challenges of elevating a time-series database from being just an IT application, used in the data center, to a critical operational technology, used throughout…