[TUHS] VM over-commit (and the OOM killers)

[segaloco via TUHS]

On Friday, February 28th, 2025 at 8:04 AM, Dennis Boone <drb at msu.edu> wrote:

> > I’m probably a lost soul on this issue, but swap space is just a way
> 
> > to turn program bugs into performance problems.
> 
> 
> You're hardly the only one. Some years ago, running Linux web and
> database servers, I quit creating swap space. A runaway program would
> turn the system into an infinite game of shuffle-the-pages well before
> the OOM killer actually decided to kill something, and in that state,
> one couldn't even reboot. This expanded the time window of "broken"
> from tens of seconds, and perhaps a service restart, into tens of
> minutes and a power button recovery. Every #$%^&* time.
> 
> De

I've read several bits of guidance lately suggesting avoiding swap due to the increasing prevalence of solid-state memories.  The assertion is that I/O heavy swapping, especially if you get into a thrashing state, is liable to age current storage technologies much more than it would have in the platter disk era.  I've heard contrary opinions that it isn't as large of a liability in reality.  I haven't settled on one or the other, I keep a swap file around on the microSD that runs my RPi, but I've only needed to swapon, like OP, when compiling gcc.

- Matt G.