On Fri, Jan 03, 2020 at 02:18:40PM -0500, Ben Cotton wrote: > https://fedoraproject.org/wiki/Changes/EnableEarlyoom > > == Summary == > Install earlyoom package, and enable it by default. This will cause > the kernel oomkiller to trigger sooner, but will not affect which > process it chooses to kill off. The idea is to recover from out of > memory situations sooner, rather than the typical complete system hang > in which the user has no other choice but to force power off. Hi, I'll throw out another idea out here, in hope that people can provide insight. It's something I wanted to look into for a while, but I admit to not having done any research myself, so the approach might be totally useless... What about using the memory controller for user units to allocate memory resources between the processes in the user session? Thanks to recent developments, the gnome session uses separate systemd units (and thus separate cgroups) for various services. We could set attributes like memory.low for "the basic components of the user session", and on the other hand, memory.swap.max for "the payload", i.e. various user processes on top. Doing something like this effectively would most likely require some changes to how we assign processes to cgroups. I still get some processes in "wrong" cgroups: │ ├─gnome-shell-wayland.service │ │ ├─1501571 /usr/bin/gnome-shell │ │ ├─1501606 /usr/bin/Xwayland :0 -rootless -noreset -accessx -core -auth /run/user/1000/.mutter-Xwaylandauth.SCXID0 -listen 4 -listen 5 -displayfd 6 │ │ ├─1501713 ibus-daemon --panel disable -r --xim │ │ ├─1501718 /usr/libexec/ibus-dconf │ │ ├─1501719 /usr/libexec/ibus-extension-gtk3 │ │ ├─1501724 /usr/libexec/ibus-x11 --kill-daemon │ │ ├─1501980 /usr/libexec/ibus-engine-simple │ │ ├─1503586 /usr/lib64/firefox/firefox │ │ ├─1503691 /usr/lib64/firefox/firefox -contentproc -childID 2 -isForBrowser ... │ │ ├─1503701 /usr/lib64/firefox/firefox -contentproc -childID 3 -isForBrowser ... │ │ ├─1503747 /usr/lib64/firefox/firefox -contentproc -childID 4 -isForBrowser ... │ │ ├─1520219 bwrap --args 35 telegram-desktop -- │ │ ├─1520229 bwrap --args 35 xdg-dbus-proxy --args=37 │ │ ├─1520230 xdg-dbus-proxy --args=37 │ │ ├─1520232 bwrap --args 35 telegram-desktop -- │ │ ├─1520233 /app/bin/Telegram -- │ │ ├─1540753 pavucontrol ... (and firefox and anything-running-as-flatpak would be the prime candidates to split out into their own cgroups and build resource limits around...) The cgroup hierarchy is mostly flat (most user services get cgroups directly in the root of the user tree under /sys/fs/cgroup/user.slice/user-nnn.slice/user@nnn.service/). To make resource assignment effective, I would like to see a "basic.slice" (name TBD) that would gather various "core" stuff like gnome-shell-wayland.service, dbus-broker.service, and whatever other services that the graphical session depends on. This would get mimimum memory protections and such. Then there should be "payload.slice", and underneath that all the non-essential services and everything that the user starts from the terminal. What I *don't know* is: how much of an overhead enabling the memory controller has, and whether those resource limits would actually have the desired effect (and more generally, how they should be best set). Zbyszek _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
