Join me on a Friday night on-call investigation into a rogue Node.js service.

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A Node.js service faced performance issues due to improper handling of worker threads, which caused high resource consumption and server instability within a Kubernetes environment. By spawning multiple workers per CPU core instead of per allocated resource, and aggressively restarting them on errors, a positive feedback loop overwhelmed both the campaign and translation services. Investigation revealed that limiting worker threads and proper resource allocation could resolve the issue, highlighting the importance of optimized worker management and enhanced observability in production environments.

Node.js and the tale of worker threads

<p>cool stuff from zalando again &lt;3</p>


<p>very good blog with detailed explanation</p>
