Boost Kubernetes Pod‑to‑Pod Performance with istio‑tcpip‑bypass and eBPF

Background

In edge and 5G scenarios, pods on the same node exchange large volumes of TCP traffic. The traditional path traverses the full kernel network stack (TCP/IP, netfilter, OVS), adding latency and limiting throughput.

Principle of istio‑tcpip‑bypass

The open‑source istio‑tcpip‑bypass plugin from Intel uses eBPF to automatically detect intra‑node TCP flows and redirects them away from the kernel stack, enabling direct socket‑to‑socket communication and reducing processing overhead.

Environment Preparation

eBPF requires a recent kernel. Ubuntu 20.04 with Linux 5.4.0‑74‑generic is recommended for the experiments.

Experiment Steps

Deploy two performance‑testing pods on the same node (use nodeSelector if the cluster has multiple nodes).

# kubectl create deployment perf --image=kubeovn/perf:dev --replicas=2
# kubectl get pod -o wide
NAME                     READY   STATUS    RESTARTS   AGE   IP          NODE
perf-...                 1/1     Running   0          ...   100.64.0.3   sealos
perf-...                 1/1     Running   0          ...   100.64.0.2   sealos

Enter one pod and start a qperf server; in the other pod start a qperf client to generate traffic.

# kubectl exec -it perf-...-b2cpv sh
/ # qperf
# kubectl exec -it perf-...-p2xpt sh
/ # qperf -t 60 100.64.0.3 -ub -oo msg_size:1:16K:*4 -vu tcp_lat tcp_bw

Deploy the istio‑tcpip‑bypass daemonset.

# kubectl apply -f https://raw.githubusercontent.com/intel/istio-tcpip-bypass/main/bypass-tcpip-daemonset.yaml

Re‑run the qperf client inside the same pod to measure the optimized path.

Test Results

The benchmarks show a 40%‑60% reduction in TCP latency across various packet sizes and a 40%‑80% increase in throughput for packets larger than 1024 bytes.

On the tested hardware, small packets (< 512 B) may see lower throughput with eBPF optimization due to default TCP‑segmentation offload settings; users should evaluate this case for workloads sensitive to small‑packet throughput.

References

istio‑tcpip‑bypass repository: https://github.com/intel/istio-tcpip-bypass

Tanzu Service Mesh Acceleration using eBPF: https://blogs.vmware.com/networkvirtualization/2022/08/tanzu-service-mesh-acceleration-using-ebpf.html/