Am 05.02.23 um 15:39 schrieb Uwe Menges:
Hi,
I just updated my backup server from Fedora 35 to 37.
After the upgrade, I tried to run amflush.
The session running amflush was killed by systemd-oomd as per these
lines in the journal:
systemd[1]: session-5.scope: systemd-oomd killed some process(es) in
this unit.
systemd-oomd[7544]: Considered 4 cgroups for killing, top candidates were:
systemd-oomd[7544]: Path: /user.slice/user-0.slice/session-5.scope
systemd-oomd[7544]: Memory Pressure Limit: 0.00%
systemd-oomd[7544]: Pressure: Avg10: 56.78 Avg60: 40.05
Avg300: 14.53 Total: 53s
systemd-oomd[7544]: Current Memory Usage: 30.0G
systemd-oomd[7544]: Memory Min: 0B
systemd-oomd[7544]: Memory Low: 0B
systemd-oomd[7544]: Pgscan: 14100751
My workaround was to "systemctl edit systemd-oomd" and add "--dry-run"
as argument
(https://www.freedesktop.org/software/systemd/man/systemd-oomd.service.html).
A "systemctl cat systemd-oomd" now has this override appended:
# /etc/systemd/system/systemd-oomd.service.d/override.conf
[Service]
ExecStart=
ExecStart=/usr/lib/systemd/systemd-oomd --dry-run
After "systemctl restart systemd-oomd", this makes the log look like
this when running amflush:
systemd-oomd[13095]: oomd dry-run: Would have tried to kill
/sys/fs/cgroup/user.slice/user-0.slice/session-3.scope with recurse=true
systemd-oomd[13095]: Considered 4 cgroups for killing, top candidates were:
systemd-oomd[13095]: Path: /user.slice/user-0.slice/session-3.scope
systemd-oomd[13095]: Memory Pressure Limit: 0.00%
systemd-oomd[13095]: Pressure: Avg10: 54.15 Avg60: 35.63
Avg300: 15.82 Total: 1min 25s
systemd-oomd[13095]: Current Memory Usage: 29.9G
systemd-oomd[13095]: Memory Min: 0B
systemd-oomd[13095]: Memory Low: 0B
systemd-oomd[13095]: Pgscan: 40620400
systemd-oomd[13095]: Last Pgscan: 40620400
And now amflush keeps running fine again.
I'm not sure what the right solution is, I just quickly wanted to get it
running again, and my itch is scratched.
Maybe something needs to be tweaked in systemd-oomd, or the amanda
package should include something to exempt amanda from systemd-oomd, or
something else.
Yours, Uwe
A quick google finds this:
https://fedoraproject.org/wiki/Changes/EnableSystemdOomd#Can_we_exclude_certain_units_from_being_killed?
So maybe you add a systemd override conf for the amanda.service (or
however it is called in F37).
You basically disabled systemd-oomd, it would have been even easier to
run "systemctl disable --now systemd-oomd", I assume.
I am not sure if amflush triggers amandad, I would have to look that up
(but I am on a train right now, so it's a bit complicated).
It should be rather easy to find the killed cgroups in the logs
somewhere. From there you might find the related service.
I am using F37 too, but currently I don't have amanda installed on these
machines.
Maybe it makes sense to come up with some fine-tuned service files and
contact the Fedora developer maintaining Amanda.
I wonder when and if this feature comes to other distros as well, I
haven't yet noticed it in Debian, for example.
regards, Stefan
