Is this really from real world experience? And is that only in certain conditions?
My experience is really the opposite from this. Thrashing was a normal occurrence on my desktop, where it went into non-recovery and a manual hard reset.
And also, with 16GB ram and 4GB swap, my running applications got moved to swap. Switching tabs in Firefox will be slow because it has to come from swap. My swappiness was set to 1 that it shouldn't swap, but it did swap always.
Now without swap and using early_oom everything is fine. When I see in /proc/vmstat that there has been a kill, it is time to reboot.
On my laptop though, my usecase is different. It only has 2GB ram, so I prefer swap over a hard kill. And I reboot it more than once a day if I am using it.
Yes, i learned it the hard way when debugging production outages. Gitlab's Praefact recommended VM sizes were too small for our usecase and we had, per provisioning defaults, no swap on all machines. 150 MB of binaries in virtual memory, only 50 MB disk cache left, this is where it made click for me.
If you want a hard OOM kill, i don't know. I'm only talking about the I/O lockup that happens in these situations.
Thank you. So ram was quite minimal, just barely enough to run the applications, and almost none left for disk io. On my laptop that is the same situation. On my desktop however, I have way more ram than needed to run the applications. So I assume it is dependent on the situation if you want (need) swap or not.
My experience is really the opposite from this. Thrashing was a normal occurrence on my desktop, where it went into non-recovery and a manual hard reset.
And also, with 16GB ram and 4GB swap, my running applications got moved to swap. Switching tabs in Firefox will be slow because it has to come from swap. My swappiness was set to 1 that it shouldn't swap, but it did swap always.
Now without swap and using early_oom everything is fine. When I see in /proc/vmstat that there has been a kill, it is time to reboot.
On my laptop though, my usecase is different. It only has 2GB ram, so I prefer swap over a hard kill. And I reboot it more than once a day if I am using it.