krunkit: Disable offloading for faster networking

[nirs]

Newer krunkit allows disabling offloading for faster networking. Keep the Offloading option in case offloading is improved in future versions.

Testing shows 6.7 times faster network performance, and 9p mount is 3 times faster.

Starting cluster:

% minikube start --driver krunkit --container-runtime containerd
😄  minikube v1.36.0 on Darwin 15.6 (arm64)
✨  Using the krunkit (experimental) driver based on user configuration
👍  Starting "minikube" primary control-plane node in "minikube" cluster
🔥  Creating krunkit VM (CPUs=2, Memory=6144MB, Disk=20000MB) ...
📦  Preparing Kubernetes v1.33.2 on containerd 1.7.23 ...
🔗  Configuring bridge CNI (Container Networking Interface) ...
🔎  Verifying Kubernetes components...
    ▪ Using image gcr.io/k8s-minikube/storage-provisioner:v5
🌟  Enabled addons: default-storageclass, storage-provisioner
🏄  Done! kubectl is now configured to use "minikube" cluster and "default" namespace by default

Testing iperf3:

% kubectl apply -f iper3-server.yaml
deployment.apps/iperf3 created
service/iperf3 created

% kubectl get deploy iperf3
NAME     READY   UP-TO-DATE   AVAILABLE   AGE
iperf3   1/1     1            1           9s

% kubectl get service iperf3
NAME     TYPE       CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
iperf3   NodePort   10.105.127.180   <none>        5201:30201/TCP   17s

% iperf3 -c $(minikube ip) -p 30201
Connecting to host 192.168.105.10, port 30201
[  5] local 192.168.105.1 port 50630 connected to 192.168.105.10 port 30201
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  1.05 GBytes  9.03 Gbits/sec
[  5]   1.00-2.01   sec  1.09 GBytes  9.29 Gbits/sec
[  5]   2.01-3.01   sec  1.06 GBytes  9.09 Gbits/sec
[  5]   3.01-4.00   sec  1.08 GBytes  9.33 Gbits/sec
[  5]   4.00-5.00   sec  1.08 GBytes  9.31 Gbits/sec
[  5]   5.00-6.00   sec  1.07 GBytes  9.23 Gbits/sec
[  5]   6.00-7.00   sec  1.09 GBytes  9.35 Gbits/sec
[  5]   7.00-8.01   sec  1.08 GBytes  9.20 Gbits/sec
[  5]   8.01-9.00   sec  1.07 GBytes  9.18 Gbits/sec
[  5]   9.00-10.01  sec  1.08 GBytes  9.28 Gbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.01  sec  10.7 GBytes  9.23 Gbits/sec                  sender
[  5]   0.00-10.01  sec  10.7 GBytes  9.23 Gbits/sec                  receiver

Testing 9p mount:

% minikube mount ~/models:/mnt/models
📁  Mounting host path /Users/nir/models into VM as /mnt/models ...
    ▪ Mount type:   9p
    ▪ User ID:      docker
    ▪ Group ID:     docker
    ▪ Version:      9p2000.L
    ▪ Message Size: 262144
    ▪ Options:      map[]
    ▪ Bind Address: 192.168.105.1:50614
🚀  Userspace file server:
ufs starting
✅  Successfully mounted /Users/nir/models to /mnt/models

📌  NOTE: This process must stay alive for the mount to be accessible ...

$ time cat /mnt/models/DeepSeek-R1-0528-Qwen3-8B-Q4_K_M.gguf >/dev/null

real    0m10.219s
user    0m0.007s
sys     0m0.263s

Requires krunkit PR:
containers/krunkit#63

And installing local libkrun-efi from main.

Status

• The krunkit PR is mostly ready
• We wait for libkrun release providing virtio features flags.
  • blocked on krun_set_gvproxy_path broken containers/libkrun#392

[k8s-ci-robot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[k8s-ci-robot]

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