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Comment by josephcsible | Hacker News Reader

To be clear, "Ubuntu 22.04's new OOM killer" is systemd. Why do we keep taking responsibilities away from the kernel and other programs that are good at handling them, only to give them to systemd for this kind of thing to happen?

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The Linux OOMKiller is inflexible and as likely to kill the right thing as the wrong thing when there's memory pressure on the system. There's a reason why third-party userspace [0] ones are used in lieu of the builtin one. You can tweak the default implementation, but never fully rely on it behaving in a deterministic manner.

Whether this systemd implementation is any better is, of course, another question entirely.

[0] https://github.com/facebookincubator/oomd

To be clear, Ubuntu 22.04's Firefox is snap Firefox, with horrible performance, so systemd decision to end its misery could be justified.

To be clear, my systemd has turned into some kind of rogue build killer daemon and my decision to end its misery feels quite justified too.

this happens with the Firefox installed as DEB package (from another repo) that isn't a snap ?

The kernel isn't good at handling OOM – to the nearest approximation it just kills whatever is using the most memory, which in my experience is almost always the thing that I least want it to kill. And it does it late enough that everything is broken anyway and the system sits thrashing forever.

All that seems to have happened here is that Ubuntu may have rolled out systemd-oomd with some overly-conservative settings, so if we could all avoid having a collective pointless shit-fit about systemd again that would be great.

> it just kills whatever is using the most memory, which in my experience is almost always the thing that I least want it to kill.

I've had the opposite experience. Usually when I'm out of memory, it's because some single process has gone crazy with memory allocation. Killing it brings the system back to "normal", but killing anything else would just lead to said crazy process gobbling up the newly-freed memory, and then being back to where I started.

> And it does it late enough that everything is broken anyway and the system sits thrashing forever.

This part I agree with.

Are we REALLY still complaining about systemd? Systemd has been one of the best things to happen to Linux.

Considering that systemd-oomd as shipped by Ubuntu is happy to start gunning processes when there are upwards of 10 GB of free memory on the system, I think those complaints are entirely justified. This is hardly the only instance of some systemd appendage presumptuously doing something obnoxious or destructive.

I am not someone who knows arcane system programming, but I use Linux since 20 years on commercial laptops, from Asus, DELL and Lenovo, etc. IMO the Linux of the 2000' where much better than today's Linux. The Linux I use are always Debian based, like Ubuntu.

For example Linux used to have a sleep mode which worked perfectly. Now it does not sleep reliably. For example if I move the mouse while it sleeps, it wakes up, even with the screen closed and uses the battery until there is no more energy in them. So the computer is unusable when I need it.

Another example is copy/paste. Today it works sometimes, some other times it paste another previous content. I use now Ubuntu 20.0.4 LTS. I just copied/pasted the version number from the system monitor panel to write this post, it pasted a previous content I copied in my browser!

A third example when I use a right click on Ubuntu's Chromium (a snap browser) then I have garbage on the screen. This browser can't display correctly non western characters.

So I do not know if its because systemd but a few years ago I used Trisquel Linux which did not used systemd at the time, and everything worked perfectly as I remember in the 2000'.

This sounds more like issues with snap (and its isolation model) than systemd.

Power issues are always a pain. I built out the Linux OS for a fleet of mobile robots and found that the defaults for power management were very poor, but everything is there to get a bulletproof system. I could see how there would be issues with more unique laptop setups or external monitors/keyboards and whatnot.

This could also just be Ubuntu. So many distros are based on Ubuntu and it’s pretty clear that Canonical doesn’t really care about Ubuntu on the desktop.

It’s little more than a sales funnel for them to make sure people use Ubuntu servers as well, at this point.

What is the best modern desktop distro? I am running Ubuntu on my newly-built "Gaming" linux box, and I am impressed with how far gaming on linux has come, but I am unimpressed with Ubuntu and Gnome Desktop.

I think Manjaro.

Arch is amazing; the newest software often works the best; the rolling model gives you new hardware support the fastest; the AUR has all the software ever (from Minecraft to the OldSchool RuneScape launcher to SVP for video interpolation); the Arch wiki is the most detailed resource ever.

But installing Arch is hard, and rarely there might be manual intervention. Enter Manjaro, which is easy to install, holds back packages for a very little while to preclude users dealing with any manual intervention breakage, has super-friendly forums (unlike Arch ;p), has an easy GUI for switching kernels and drivers, and yet has the AUR and can benefit from Arch wiki since it's Arch-based.

In my experience, both Arch and Manjaro have worked way better than Ubuntu (in terms of freezes and crashes), which seemed deeply paradoxical.

>I am unimpressed with Ubuntu and Gnome Desktop.

GNOME 3 is a laptop/tablet DE. It barely supports multiple monitors, unlike KDE, which is foremost a *desktop* DE. Amazing panel (aka taskbar), multimonitoring is a first-class concern (you can game on one monitor while you have a panel with tray that can have your CPU/GPU temps and the time on the other), deeply customizable, and my favorite bit is that you can disable desktop composition in its settings. Why? Because that makes it buttery smooth, which extends to games. Try dragging a window around with your mouse on a >=120 Hz monitor with composition on and then off to see what I'm talking about. (And all you lose by turning it off is terminal transparency.) In GNOME, of course, doing this is impossible (or at least extremely esoteric; it's not a setting).

GNOME and KDE are the two most polished DEs out there, but only one of them is a desktop DE. :p

I would be curious if Ubuntu is doing anything on top of it, though. systemd's oom-killer has been enabled in Fedora for like a year now, IIRC, and no one on Fedora has complained about it killing their Firefox browser or their entire DE session.

If you search there are many complaints of Fedora killing applications under similar circumstances. Ubuntu sets the memory pressure limit to 50% and Fedora does the same for user processes. The systemd-oomd default is a less aggressive 60%.

To be clear the kernel is horrible at handling OOM situations and Ubuntu's configuration of systemd-oomd is more aggressive at deciding when to start killing things than the default systemd-oomd settings.

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