Keynote: How One Line of Code Freed 30,000 CPU Cores: Deep-Diving Fluent Bit at Petabyte... F. Ponce

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Keynote: How One Line of Code Freed 30,000 CPU Cores: Deep-Diving Fluent Bit at Petabyte Scale - Fabian Ponce, Member of Technical Staff, OpenAI

Processing 9+ petabytes of logs daily, OpenAI's Kubernetes fleet was maxed out; throttling events were dropping critical logs and there was no more CPU to allocate. Using perf to profile Fluent Bit revealed an unexpected culprit: millions of unnecessary syscalls from inotify's interaction with line-by-line log flushing. A one-line configuration change cut CPU usage by 50%, freed 30,000 cores for other workloads, and eliminated the largest source of throttling events. Learn how understanding tools at the system level unlocks optimizations that benefit everyone, and why OpenAI is contributing this fix upstream to the CNCF community.