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Operating Model

The default Stakkr model reserves a small CPU set for host and emulator work, puts guest vCPUs in a shared execution pool, and uses relative weights for Gold, Silver, and Bronze contention behavior.

CPU Policy

SettingDefault
Host reserve0-1
Host housekeeping0-1
Emulator CPUs0-1
Guest execution pool2-11
Gold CPUWeight512
Silver CPUWeight333
Bronze CPUWeight167

The weighted performance domains are relative contention domains. They are not hard reservations.

Memory Policy

SettingDefault
zram devicezram0
zram size16G
zram compressionzstd
THP modemadvise
THP defrag modemadvise
KSM run1

The memory policy is applied by the host memory oversubscription playbook and verified by the status command.

Live VM Policy

The live shared execution-pool path currently targets these managed workers:

VMTier
kvm-worker-01Gold
kvm-worker-02Silver
kvm-worker-03Bronze

The managed workers must already exist before shared-execution-pool-apply can shape their live systemd scopes and libvirt CPU pinning.

Separate Experiment

Clock frequency tiering is a separate experiment. It uses dedicated CPU lanes and per-lane max-frequency caps instead of the default shared execution-pool model.