Not quite what happens. OpenBSD doesn’t kill processes that use too much memory—it just causes any more memory allocation to fail. A well‐written program would detect that out‐of‐memory condition and try to handle it (maybe pause, or print a message to the user, or exit cleanly), but Firefox is not well‐written, and just crashes…<p>On the other hand, on Linux allocations succeed even when there isn’t enough memory on the system, and the OOM killer will kill a process once it starts <i>using</i> too much memory. Unlike the OpenBSD way, there’s no way for a process to detect that it’s using too much memory and handle it gracefully—you have to trust that the OOM killer is intelligent enough to never kill the wrong program…