Welcome to my Internet corner!
I've been a backend engineer and Open Source enthusiast for quite a while now. I sometimes do interesting, funny or stupid things with computers; but I rarely post about them 馃う. But when I do, it's here.
Using exceptions for flow control is slow, even for DateTimeFormatter
Last week, I reviewed a seemingly simple patch to an Apache Crunch pipeline. Functional details don鈥檛 matter, but the pipeline processes loads of hits from HTTP proxies. Hits have a timestamp and the patch aims to enrich every hit with some metadata indexed by user and business date (ie. we query a repository with a composite key, part of it is the date formatted as a yyyyMMdd string). Functional requirements are clear, the code is simple and the repository is more than fast enough to not affect the performance profile of the pipeline...
Chasing down Guava cache slowness
This post describes how I re-discovered a three year old performance issue in Guava caches.
Presentation, Sample 'em all
This post share the slide deck I used to introduce flamegraphs and Java profilers to other teams when I joined Mediam茅trie and reduced the execution time of several data pipelines by 100x or more.
OpenJDK JEP 180: HashMap vs collisions
This post explains how OpenJDK JEP 180 reworks HashMap implementation to mitigate complexity attacks.