feat: add guest-to-host time synchronisation - #2364
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What kind of change does this PR introduce?
Fixes KUBE-1282.
For v3 qemu images, add guest-to-host time synchronisation.
This ensures that the time between the host and guest does not drift. This uses less resources than the full NTP stack because this uses the Linux PTP_KVM device and does not require network access.
What is the current behavior?
The default
arch_sys_counterclock source is used, which loses ~3s of accuracy a day. A pod running for ~1 year is about 15mins off.systemd-timesyncdis installed on the node, but several (~200) pods had NTP sync errors.With such a large drift, all backups will fail.
What is the new behavior?
We will maintain a constant time sync between guest-and-host even with network disruptions.