Kernel

Linux overcommit policy controls admission of certain virtual-memory commitments. It is separate from allocating resident physical pages, choosing an OOM victim, and enforcing a container’s memory limit. A successful allocation can precede physical demand, but that does not make all allocations free or guarantee that later accesses will succeed under every resource constraint. ...

On Linux, sysctl exposes selected kernel parameters through /proc/sys. It can inspect the running state, and an authorized write can change that state without rebooting. A configuration file is a separate instruction to a loader. Confusing these two layers produces a familiar incident: the desired value is on disk, but the kernel is doing something else. ...