Consider a situation where some process starts using excessive amounts of memory, due to a bug or a misconfiguration or other such reason. Swap can be bad in that it may make some failure cases last longer. To clarify: RAM/swap ratio or whether or not swap should be allocated in the first place is out of scope of the question.

Prompted by user10489's answer: *NIX-like OS:s don't have a separate hiberfile similar to what Windows uses?.

Does having a separate swap partition instead of a swap file change the situation?.

Can someone give some real life examples from the UNIX/Linux world when having a swap file in a system with large amounts of RAM actually can cause / did cause unwanted consequences, and what those consequences could be / would have been?.

At this point many Linux users decide to not swap at all, but I've reserved 16GB just in case - drive space is cheap but the classic swap = 2x RAM seems exaggerated.

For example my Linux box has 64GB of RAM which allows me to run multiple VMs simultaneously. However that's how far I get, the actual facts remain elusive. Dropping the memory space foo uses to swap would slow down the access to it slowing foo itself down causing warnings, errors or even a total failure.

I can imagine a background-running application or service foo whose correct functionality depends on instant memory access. Then there are obviously countering arguments such as expressed here. That comes up often in conjunction with 'if you have X GB of RAM or more you don't need a swap', usually backed by credible arguments. In discussions about swap files ('should I create one?') I often see an obscure mention along the lines 'in certain situations swap file can do more harm than good'.

How much free space for os x swap