On my desktop system, most of my problems with swap come from dealing with the aftermath of an out-of-control process eating all my RAM. In this case, the offending program demands memory so quickly that everything from legitimate programs gets swapped out. These programs proceed to run poorly for the next several minutes to an hour depending on usage, since the OS only swaps pages back in once they are referenced, even if there is plenty of free space not even being used in the disk cache.
Eventually I wrote a small script that does the equivalent of "sudo swapoff -a && sudo swapon -a" to eagerly flush everything to RAM, but I was surprised by how many people seemed to think there's no legitimate reason to ever want to do so.
Eventually I wrote a small script that does the equivalent of "sudo swapoff -a && sudo swapon -a" to eagerly flush everything to RAM, but I was surprised by how many people seemed to think there's no legitimate reason to ever want to do so.