Runc: cgroup2: systemd manager uses deprecated options

[AkihiroSuda]

https://github.com/opencontainers/runc/blob/e57a774066af2f0adc76ffb6201588091cd872d5/libcontainer/cgroups/systemd/unified_hierarchy.go#L99-L132

According to systemd.resource-control(5), CPUShares, MemoryLimit, and BlockIOWeight are deprecated

[AkihiroSuda]

cc @filbranden

[filbranden]

Yeah but there's little we can do at this point since we need to be compatible all the way back to systemd v219 + backports in RHEL 7...

For the future, my idea was to fix https://github.com/systemd/systemd/issues/12460 by possibly introducing a new D-Bus API and then using that API when available (that would also serve as detection that systemd is new enough.)

I think it's probably too late for systemd v244, but I hope to make it in time for the next version. (Also, support for freeze, etc. are all landing on systemd around now...)

Cheers!
Filipe

[AkihiroSuda]

I think unified manager can depend on recent version of systemd (v242-v243). RHEL 7 doesn't support unified mode.

[filbranden]

Yes! Definitely agree with that for "unified" driver.

[rhatdan]

RHEL7 will never support cgroups V2, so that makes sense.