Ubuntu 22.04 LTS Has A Change On The Way For Systemd-OOMD Being Kill-Happy With Apps

This month Ubuntu developers have been trying to figure out how to best deal with systemd-oomd on Ubuntu 22.04 LTS killing applications like Firefox during high memory/swap use and that leading to a poor user experience when desktop users not being aware of the situation and suddenly finding their software killed.

Ubuntu developers have been evaluating different options for better dealing with systemd's out-of-memory daemon (OOMD) and have a fix on the way for Ubuntu 22.04 LTS users currently in the proposed archive.

The Ubuntu issue has been tracked as systemd-oomd frequently kills Firefox and Visual Studio Code.

With systemd 249.11-0ubuntu3.4 currently in the Jammy proposed archive but should be out shortly as a stable release update, "ManagedOOMSwap=auto" is now being set on the root slice (-.slice). To now with Ubuntu 22.04 LTS it had been using ManagedOOMSwap=kill. In other words, Ubuntu 22.04 is disabling swap kill by default and thus limiting the systemd-oomd default behavior on Ubuntu Linux to monitoring memory pressure but not the swap usage.

In not killing on heavy swap usage, this seems to improve the user experience of not finding applications killed unexpectedly and also saves them from one of the other proposals of increasing the default swap size on Ubuntu, among other ideas that have been explored.