In my experience, I think engineering swap usage is more complex than this article leads on. While adding more swap may make sense for many systems, I've person

In my experience, I think engineering swap usage is more complex than this article leads on. While adding more swap may make sense for many systems, I've personally worked on several systems where disabling swap made a huge difference. It's just one of those things where there isn't a hard rule. One of the issues I've encountered more than once with Java software, is what appears to be longer than expected pauses in the GC, that I've linked to swap usage. The theory is, if you have a reference that lives long enough to get promoted to an old generation, but then is released, the memory in question won't be used for quite some time. This can lead the kernel to detect the memory pages not being used, swap them to disk, but then when it's time to do GC, the process is just frozen while the GC is running and get's backed up. Depending on the workload this might be fine, however, on both the platforms I encountered this issue on, were real time applications which were engineered to have available memory for the application and did (and also had no benefit from using the free'd memory for IO cache). So in this case, disabling swap had a real and measurable performance boost for us, getting rid of some of the variability in our GC runtime and pauses. Under low memory conditions I think is also subjective. So if I'm a distributed / highly available system that's doing message routing in a telco environment, I would rather have the OOM killer kill the process, and failover to a backup, then for the system to be up but unresponsive because it's spending a majority of it's time swapping too/from disk. Again, this totally depends on the platform.