Open-sourcing oomd, a new approach to handling OOMs

What this post added

Introduced 'oomd', a userspace Out-Of-Memory (OOM) killer that replaces the traditional Linux kernel OOM killer. oomd utilizes Pressure Stall Information (PSI) for resource monitoring and cgroup2 for process accounting. It features pre-OOM hooks for early detection and a plugin system for custom OOM handling policies, offering faster, more flexible, and reliable OOM management compared to the kernel-based approach. This has led to the elimination of 30-minute livelocks in production environments.