You CAN hard fail, but not overcommitting can severely limit the system in the very common case where you fork and exec. See e.g. https://lwn.net/Articles/7854

You CAN hard fail, but not overcommitting can severely limit the system in the very common case where you fork and exec. See e.g. https://lwn.net/Articles/785430/ https://lwn.net/Articles/785430/