From Fedora Project Wiki
No edit summary |
No edit summary |
||
| Line 27: | Line 27: | ||
* Make sure to clean up the override and reset the test unit when you're done: | * Make sure to clean up the override and reset the test unit when you're done: | ||
<pre> | <pre> | ||
sudo rm /etc/systemd/system/-.slice.d/ | sudo rm -rf /etc/systemd/system/-.slice.d/ | ||
sudo systemctl daemon-reload | sudo systemctl daemon-reload | ||
systemctl --user reset-failed systoomd_mempressure_test.service | systemctl --user reset-failed systoomd_mempressure_test.service | ||
Revision as of 02:20, 17 March 2021
Description
This test case tests that systemd-oomd will kill a cgroup with the most pgscans when memory pressure on user@$UID.service exceeds 10% (or whatever was defined in systemd-oomd-defaults).
Setup
- This test case should be performed on either bare-metal or virtual machines.
- Check that you are running systemd 248~rc1 or higher with
systemctl --version. - Ensure the systemd-oomd-defaults package is installed (included with Fedora 34).
- You will also need to install
stress-ng. - Boot the system and log in as a regular user.
- So as not to trigger the swap policy for systemd-oomd, create an override with the following commands (don't forget to remove this file and
systemctl daemon-reloadto restore the settings afterwards):
sudo mkdir /etc/systemd/system/-.slice.d/ printf "[Slice]\nManagedOOMSwap=auto" | sudo tee /etc/systemd/system/-.slice.d/99-test.conf sudo systemctl daemon-reload
How to test
- Check that systemd-oomd is running:
systemctl status systemd-oomd
- Check that the systemd-oomd-defaults policy was applied by running
oomctland verifying that "/user.slice/user-$UID.slice/user@$UID.service/" is listed as a path under "Memory Pressure Monitored CGroups" along with some stats. "Swap Monitored CGroups" should show no paths since we put in an override. - Now run the test:
systemd-run --user -r --unit systoomd_mempressure_test /usr/bin/stress-ng --brk 1 --stack 1 --bigheap 1 -t 90s
- Make sure to clean up the override and reset the test unit when you're done:
sudo rm -rf /etc/systemd/system/-.slice.d/ sudo systemctl daemon-reload systemctl --user reset-failed systoomd_mempressure_test.service
Expected Results
- The system becomes unresponsive during the test but should respond again once
stress-ngis killed. - systemd-oomd will have killed systoomd_mempressure_test.service after about 10 seconds.
stress-ngwill timeout after 90 seconds, so if the the command runs to timeout, it means systemd-oomd did not kill it. You can verify by checking for log lines that say something about "Memory pressure for <...> and there was reclaim activity" and "systemd-oomd killed <...> process(es)" withjournalctl.