[_ph_]

The point being is, that a system doesn't have to misbehave to allocate more memory than the total RAM. And in those cases, there is a very good reason to have swap space, and swapping won't impact the performance of the system - rather the opposite.

[AstralStorm]

Sure it does misbehave. The memory allocation failures should be handled properly and by that I mean not by crashing. Very few applications should require memory use beyond current free RAM. Especially not JVM, JavaScript VM, a web browser or even video player. Yet this silly heuristics in Linux lets it happen.

[_ph_]

No, that is not correct. If you have any idle processes, their memory can safely swapped out without impacting performance. The user should not be forced to quit programs as soon as they become idle. Also, as described in the article, a program often allocates pages, which also become unused and can be swapped out. In an ideal world, a program would not allocate pages which become idle, but that happens with complex software (and often depends on the user interaction, and thus is not completely predictable). Swapping out idle pages is a very simple solution to make more memory available for the active processes.