20 years ago on Windows 98 it just started swapping, but it was no big deal. If something became too slow to be usable, you could just press ctrl+alt+del and kill that swapped program and everything worked fine afterwards.
On the other hand, my modern linux laptop, it starts swapping, and it swaps and swaps and you can do nothing, not even move the mouse, till 30 minutes later something crashes.
At that time, swapping out a 4k page was a significant part of memory: 4k of 16 MiB is 1/4096 of memory. Each swap gets back a lot of memory the program needs. Now the swap is still 4k pages, but memory has expanded by a thousand fold. Basically swap is a thousand times worse today than it was in the time of Windows 98.
For harddrives swap isn't used now to expand memory, it's used to remove initialization code and other 'dead' memory. Swap should be set to only a tiny fraction of the memory size for this reason, to prevent it from being used to handle actual out-of-memory conditions. But realistically for most users it's not even worth enabling at all because of the occasional memory that needs to be swapped in from disk.
For SSDs the seek speed has improved to match the extra memory so swap can still be used like in the old days to expand the effective memory size. But memory is so large a swap file that's a fraction of memory size to offload 'dead' memory is enough unless there's a specific reason to actually use swap for out-of-memory.
I feel like Linux has, in general, from a UX point of view, the worst behaviour when swapping and the worst behaviour in general under memory pressure.
I feel like it has gotten worse over time, which might not be just the kernel but the general desktop ecosystem. If you require much more memory to move the mouse or show the task manager equivalent, then the system will be much less responsive when it thrashes itself.
Honestly, I'ld much rather have Linux just crash and reboot, that'd be faster than it's thrashing-tantrums.
Luckily, there's earlyoom, which just rampages the town quickly if memory pressure approaches. Like a reboot (ie. damage was done), just faster.
In any case, it makes me sad (in a bad way) to see how bad the state of things is when it comes to the basics of computing, like managing memory.
i3 ≥ v4.13 will pick up this value from the Xft.dpi resource in ~/.Xresources as well, which is the more common way of configuring DPI.
edit: haven’t tested this within Xwayland, though. Note that i3 is only supported on X11.
Yep. I bought a second computer for full browsers. One for dev, another for 'full' browsing (Javascript on) and on my i3 dev machine, I only have NoScript browsing on for dev stuff.
I suppose it might be possible to whip something up with cgroups and policy that will keep the VT, bash, X and a few select programs always resident in memory and give them ultimate I/O priority, but I haven't tried.
Default settings for dirty ratio and dirty background ratio exacerbate the issue: more data is held onto before it is written, and once the background ratio is hit, any application writing to disk will block.
EDIT: see comment below for more accurate numbers.
>A typical reference to RAM is in the area of 100ns, accessing data on a SSD 150μs (so 1500 times of the RAM) and accessing data on a rotating disk 10ms (so 100.000 times the RAM.
Latency Numbers Every Programmer Should Know
https://kernelnewbies.org/Linux_4.10#head-f6ecae920c0660b7f4...
sudo swapoff -a sudo swapon -a