Kubernetes Gateway API vs. Ingress-NGINX: Envoy Gateway & Cilium eBPF Migration Benchmarks (2026 Playbook)

# Kubernetes Gateway API vs Ingress NGINX Benchmarks: Envoy Gateway & Cilium eBPF Migration (2026 Playbook)

Summary: Comparing Kubernetes Gateway API against Ingress-NGINX benchmarks demonstrates how modern data-plane architectures resolve fundamental scaling bottlenecks. By replacing monolithic NGINX process reloads with dynamic Envoy xDS state synchronization and Cilium eBPF kernel socket switching (sockops), engineering teams eliminate worker reload connection drops, suppress tail latency spikes, and stabilize CPU and memory utilization under heavy route churn. Includes production migration manifests, architectural performance telemetry, and zero-downtime cutover protocols.

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The Architectural Impasse of Ingress-NGINX at Modern Scale

The community-driven kubernetes/ingress-nginx controller has served as the default ingress tier for Kubernetes deployments for nearly a decade. However, under high-density microservice architectures, rapid continuous deployment (CD) pipelines, and sustained traffic loads exceeding 50,000 requests per second (RPS), the underlying design of Ingress-NGINX exhibits fundamental architectural bottlenecks that cannot be resolved through CPU scaling or memory allocation alone.

Monolithic Configuration Generation and the SIGHUP Penalty

The core operational model of Ingress-NGINX relies on synchronizing state from the Kubernetes API server into a flat, monolithic configuration file located at /etc/nginx/nginx.conf. Whenever an engineer adjusts an Ingress resource, modifies an endpoint via an EndpointSlice update, or performs a canary rollout, the ingress controller triggers a synchronization sequence:

1. The controller receives watch events from the Kubernetes API server.

2. A Go template parser reconstructs the entire global nginx.conf document in memory.

3. The controller executes nginx -t in a child process to validate syntax across thousands of lines.

4. If validation passes, the controller issues a SIGHUP signal (nginx -s reload) to the NGINX master process.

[K8s API Event] -> [Re-render nginx.conf] -> [nginx -t] -> [SIGHUP] -> [Fork New Workers] -> [Drain Old Workers]
                                                                              │
                                                                   Epoll lock contention
                                                                   Transient TCP RSTs
                                                                   Validation & fork CPU burst

At low deployment frequencies, this reload mechanism is manageable. In high-frequency enterprise environments where multiple development teams deploy dozens of microservices per hour, EndpointSlice updates generate continuous reload loops.

During an NGINX reload, the master process spawns an entirely new generation of worker processes while leaving the old workers alive to drain active client connections (worker_shutdown_timeout). Under persistent HTTP/1.1 keep-alive and HTTP/2 multiplexed streams, old workers linger for minutes. As new reloads occur before existing workers finish draining, worker processes accumulate, depleting system file descriptors (nofile), saturating memory, and causing severe lock contention on Linux epoll listeners. Incoming TCP handshakes queue in the listen() backlog, culminating in packet drops, TCP resets (ECONNRESET), and upstream HTTP 502/504 errors.

The Security and Governance Crisis of Annotation Sprawl

Beyond operational stability, Ingress resources suffer from structural governance failures. The original networking.k8s.io/v1 Ingress specification lacks expressive primitives for modern layer-7 traffic management. Capabilities such as URL rewrites, custom header manipulation, rate limiting, and canary routing rely on unstructured, stringly-typed annotations (nginx.ingress.kubernetes.io/*).

This annotation model collapses operational boundaries:

• No Role-Based Access Control (RBAC) Isolation: A developer deploying an application in a tenant namespace can inject directives such as configuration-snippet or server-snippet. In multi-tenant environments, unvalidated configuration snippets can compromise controller isolation, as documented in historical Ingress-NGINX security advisories (including CVE-2021-25742 and CVE-2022-4886) where custom snippet directives permitted privilege escalation beyond tenant namespace boundaries.
• Brittle Regex Compounding: Composing URL rewrites across multiple microservices requires complex regular expression captures (rewrite-target: /$2). Because annotations are not checked by the Kubernetes schema validation engine at compile time, an invalid regex deployed to a single route can fail the entire nginx.conf validation phase, halting route updates across unrelated production teams.

The Kubernetes Gateway API (gateway.networking.k8s.io/v1) directly addresses these structural failures through a role-oriented, expressive, and strictly typed architecture.

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Architectural Comparison: Edge Reverse Proxy vs. In-Kernel eBPF Routing

Transitioning from Ingress-NGINX to modern Gateway API implementations changes the data plane from static file reloads to dynamic state synchronization, and in advanced implementations, to in-kernel socket splicing.

flowchart TD
    subgraph Traditional_Ingress_NGINX["Traditional Ingress-NGINX Architecture"]
        A1["Client Packet (SYN/ACK)"] --> B1["Host Physical NIC"]
        B1 --> C1["Netfilter / Iptables PREROUTING (NAT)"]
        C1 --> D1["Conntrack Table Lookup & Mutation"]
        D1 --> E1["veth Pair / Bridge Traversal"]
        E1 --> F1["Ingress Pod: Userspace NGINX Worker"]
        F1 -->|"Monolithic Reload (SIGHUP)"| G1["nginx.conf Re-parsed"]
        F1 --> H1["veth Pair Out to Host"]
        H1 --> I1["KUBE-SERVICES Iptables Chain"]
        I1 --> J1["Target Pod veth"]
        J1 --> K1["Application Container Socket"]
    end

    subgraph Cilium_eBPF_Gateway["Cilium eBPF & Envoy Gateway Architecture"]
        A2["Client Packet (SYN/ACK)"] --> B2["Host Physical NIC"]
        B2 --> C2["eBPF XDP / TC Ingress Hook"]
        C2 -->|"Direct BPF Sockops / Sockhash Map"| D2["In-Kernel Socket Splicing"]
        D2 --> E2["Target Pod Socket"]
        C2 -.->|"L7 Policy / TLS Inspection Needed"| F2["Envoy Data Plane (xDS Streaming)"]
        F2 -.->|"No Reloads / Dynamic Memory Swaps"| E2
    end

1. Traditional Edge Reverse Proxy (`ingress-nginx`)

In standard Ingress-NGINX deployments, every packet undergoes multiple traversals between kernel space and user space. Incoming traffic encounters Linux netfilter tables and iptables rules generated by kube-proxy. The kernel tracks every connection via the nf_conntrack subsystem. Traffic crosses virtual ethernet (veth) boundaries to enter the NGINX pod, where worker processes buffer bytes into user space before establishing a secondary TCP connection across another veth pair through iptables service chains to the target pod.

2. Envoy Gateway (Dynamic xDS Engine)

Envoy Gateway replaces file-based reloads with the dynamic Envoy Discovery Service (xDS) API over streaming gRPC. Configuration domains are segmented into independent APIs:

• LDS (Listener Discovery Service): Binds ports and downstream TLS certificates.
• RDS (Route Discovery Service): Dynamically injects route trees, header modifiers, and rewrites.
• CDS (Cluster Discovery Service): Manages upstream backend service pools.
• EDS (Endpoint Discovery Service): Tracks individual pod IP additions and deletions.

When an HTTPRoute or backend pod changes, Envoy Gateway transmits a binary protobuf update over gRPC. Envoy applies the modification via atomic pointer swaps in its internal configuration trees. Active worker threads continue processing live traffic without dropped connections, socket recreation, or process forks.

3. Cilium Gateway API (eBPF In-Kernel Data Path)

Cilium takes Gateway API performance further by replacing the traditional netfilter/iptables datapath with extended Berkeley Packet Filter (eBPF) programs attached directly to network drivers via XDP (eXpress Data Path) and TC (Traffic Control).

For layer-4 forwarding and node-local routing, Cilium executes sock_ops BPF programs. By intercepting TCP state transitions (BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB) and populating a BPF_MAP_TYPE_SOCKHASH socket map, Cilium bridges the sender socket directly to the receiver socket in the Linux kernel. When packets arrive for an established connection, Cilium bypasses the entire TCP/IP network stack, avoiding iptables evaluation, nf_conntrack table contention, and veth pair context switching. When Layer-7 manipulation (TLS termination, header transformation, prefix rewrite) is explicitly required, Cilium redirects traffic to its embedded Envoy proxy instances with minimum kernel-to-user space transitions.

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Performance Benchmarks: High-Concurrency Stress Testing Under Continuous Route Churn

Evaluating real-world stability across Ingress-NGINX, Envoy Gateway, and Cilium Gateway API requires measuring latency distribution, CPU consumption, and route convergence behavior under continuous configuration churn and high-concurrency traffic profiles.

Test Environment and Methodology

• Cluster Architecture: Multi-node Kubernetes v1.32 cluster running on modern Linux (Ubuntu LTS, Kernel 6.8, 16 vCPU, 32 GB RAM per worker node).
• Load Generation Harness: Distributed HTTP/1.1 and HTTP/2 benchmarking using open-source tools (fortio and wrk2) targeting simulated upstream Go microservices returning 2 KB JSON payloads with 1 ms simulated backend latency.
• Workload & Route Churn Profile: High sustained concurrency (50,000 requests per second target throughput) evaluated while background automation continuously modifies canary traffic weights and routing paths to simulate rapid deployment cycles.

Latency and Throughput Benchmark Profiles

Tail Latency Behavior Under Continuous Route Churn (Relative Scale)

Ingress-NGINX      [██] p50 Steady-State    [████████████] p95 Reload Contention    [████████████████████████████████] p99 Worker Drain Spikes
Envoy Gateway      [█] p50 Steady-State     [███] p95 Atomic Swap                   [█████] p99 Deterministic RDS
Cilium eBPF        [░] p50 Socket Bypass    [██] p95 In-Kernel Routing              [████] p99 Direct Dispatch

Architectural Analysis of Benchmark Telemetry

1. Tail Latency Suppression: Ingress-NGINX experiences pronounced p99 and p99.9 tail latency inflation whenever configuration churn occurs. This degradation stems directly from worker process turnover. As old workers yield CPU cycles to drain active connections, the NGINX master process expends significant CPU cycles validating configuration buffers and coordinating worker forks, creating lock contention on shared listening sockets. Conversely, Envoy Gateway avoids tail spikes through lock-free atomic pointer swaps in RDS route trees, while Cilium Gateway API bypasses intermediate socket layers entirely by offloading connection routing directly into eBPF socket maps.

2. CPU and Memory Stability: Under rapid route modifications, Ingress-NGINX exhibits severe CPU spikes caused by repetitive Go template re-rendering, nginx -t validation forks, and process lifecycle management. Concurrently, memory usage escalates because multiple generations of worker processes temporarily coexist in memory during connection drain cycles. In contrast, Envoy Gateway and Cilium process route changes as incremental protobuf updates over streaming gRPC, maintaining flat, deterministic CPU and memory profiles regardless of deployment velocity.

3. Packet Loss and Error Elimination: In high-concurrency environments with long-lived connections (HTTP/1.1 keep-alive and HTTP/2 multiplexing), Ingress-NGINX worker draining frequently exhausts worker timeouts or listen backlogs, precipitating transient TCP resets (ECONNRESET) and HTTP 502 Bad Gateway responses. Both Envoy Gateway and Cilium Gateway API eliminate process-reload packet drops: existing client connections remain bound to active worker threads or kernel sockets while new traffic immediately routes to updated endpoints via in-memory pointer swaps.

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Manifest Migration: Translating Annotation Sprawl to Clean Gateway API CRDs

The fundamental design shift in the Kubernetes Gateway API is the separation of responsibilities into three distinct roles:

1. Infrastructure Provider: Manages the GatewayClass.

2. Platform Operator: Deploys and governs the Gateway (listeners, TLS certificates, network policies).

3. Application Developer: Deploys HTTPRoute resources to define path routing, header modification, and traffic shifting.

Legacy Ingress-NGINX Configuration Manifest

The following manifest demonstrates a typical production Ingress-NGINX configuration, featuring brittle annotations for header manipulation, path rewrites, canary traffic weighting, and SSL redirects:

  # legacy-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: order-service-ingress
  namespace: production
  annotations:
    kubernetes.io/ingress.class: "nginx"
    nginx.ingress.kubernetes.io/ssl-redirect: "true"
    nginx.ingress.kubernetes.io/backend-protocol: "HTTP"
    nginx.ingress.kubernetes.io/proxy-connect-timeout: "5"
    nginx.ingress.kubernetes.io/proxy-read-timeout: "15"
    nginx.ingress.kubernetes.io/use-regex: "true"
    nginx.ingress.kubernetes.io/rewrite-target: "/v2/$2"
    nginx.ingress.kubernetes.io/configuration-snippet: |
      more_set_headers "X-Forwarded-Proto: https";
      more_set_input_headers "X-Platform-Client: internal-mesh";
      proxy_set_header X-Transaction-ID $request_id;
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "20"
spec:
  tls:
    - hosts:
        - api.wisehustlers.internal
      secretName: api-tls-cert
  rules:
    - host: api.wisehustlers.internal
      http:
        paths:
          - path: /orders(/|$)(.*)
            pathType: ImplementationSpecific
            backend:
              service:
                name: order-service-v1
                port:
                  number: 8080

Declarative Kubernetes Gateway API Manifests

To migrate this setup cleanly, the configuration is divided into structured resources conforming to the standard gateway.networking.k8s.io/v1 API.

GatewayClass Resource (Platform Infrastructure)

  # 01-gatewayclass.yaml
apiVersion: gateway.networking.k8s.io/v1
kind: GatewayClass
metadata:
  name: cilium-gateway-class
spec:
  controllerName: io.cilium/gateway-controller
  description: "Cilium eBPF Host-Routing Data Plane Controller"

Gateway Resource (Platform Operator Listener)

The Gateway resource establishes the ingress entry point, binds TLS certificates, and restricts which namespaces may attach routes to the domain:

  # 02-gateway.yaml
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: internal-edge-gateway
  namespace: infra-gateways
spec:
  gatewayClassName: cilium-gateway-class
  listeners:
    - name: https-api
      protocol: HTTPS
      port: 443
      hostname: "api.wisehustlers.internal"
      tls:
        mode: Terminate
        certificateRefs:
          - kind: Secret
            name: api-tls-cert
      allowedRoutes:
        namespaces:
          from: Selector
          selector:
            matchLabels:
              env: production

HTTPRoute Resource with Native Filters (Application Team)

The HTTPRoute defines matching rules, replaces regex string injection with native filters (URLRewrite and RequestHeaderModifier), and configures declarative canary traffic splitting without fragile auxiliary annotations:

  # 03-httproute.yaml
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: order-service-route
  namespace: production
spec:
  parentRefs:
    - name: internal-edge-gateway
      namespace: infra-gateways
  hostnames:
    - "api.wisehustlers.internal"
  rules:
    - matches:
        - path:
            type: PathPrefix
            value: /orders
      filters:
        # Native Request Header Manipulation (replaces configuration-snippet)
        - type: RequestHeaderModifier
          requestHeaderModifier:
            set:
              - name: X-Platform-Client
                value: "internal-mesh"
              - name: X-Forwarded-Proto
                value: "https"
            add:
              - name: X-Gateway-Engine
                value: "Cilium-eBPF"
        # Native Path Rewriting (replaces rewrite-target regex)
        - type: URLRewrite
          urlRewrite:
            path:
              type: ReplacePrefixMatch
              replacePrefixMatch: /v2
      # Native Traffic Splitting (replaces canary-weight annotations)
      backendRefs:
        - name: order-service-v1
          port: 8080
          weight: 80
        - name: order-service-v2
          port: 8080
          weight: 20

---

Step-by-Step Migration Strategy: Zero-Downtime Traffic Cutover

Migrating production infrastructure handling critical transactions demands an incremental cutover strategy. Engineering teams executing migrations at scale frequently engage specialist platform advisory partners such as Wise Hustlers Cloud & DevOps Engineering to architect migration pipelines, validate eBPF kernel compatibility, and execute zero-downtime cutovers without operational disruption.

Phase 1: Dual-Stack Controller Deployment

Deploy the Gateway API Custom Resource Definitions (CRDs) and instantiate your chosen Gateway controller alongside the existing Ingress-NGINX controller:

  # Install Standard Gateway API CRDs v1.2.0
kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v1.2.0/standard-install.yaml

  # Verify CRD registration
kubectl get crds | grep gateway.networking.k8s.io

Confirm that the new Gateway controller provisions a dedicated Layer-4 Cloud Load Balancer (such as an AWS NLB or Google Cloud Regional Passthrough LB) without modifying any existing Ingress-NGINX IP allocations.

Phase 2: Route Shadowing and Verification

Before routing live production requests, validate that your HTTPRoute rules accurately match upstream paths and header transformations. Use the native RequestMirror filter to duplicate live traffic from production to a staging validation instance:

  # snippet inside HTTPRoute rules.filters
- type: RequestMirror
  requestMirror:
    backendRef:
      name: order-service-shadow
      port: 8080

Verify that response status codes and upstream application logs match identically across both paths.

Phase 3: DNS Weighted Cutover

Execute the traffic transition at the external DNS tier (Amazon Route 53, Cloudflare, or edge BGP Anycast):

DNS / CDN Ingress (api.wisehustlers.internal)
            │
    ┌───────┴───────┐
 90%│            10%│ (Incrementally shifted to 100%)
    ▼               ▼
[Ingress-NGINX]  [Gateway API (Envoy/Cilium)]
    │               │
    └───────┬───────┘
            ▼
   [Backend Microservices]

1. Shift 5% of production traffic to the Gateway API Load Balancer.

2. Monitor latency distribution, connection reset counters, and error rates for 30 minutes.

3. Advance traffic weights: 10% $\rightarrow$ 25% $\rightarrow$ 50% $\rightarrow$ 100%.

Phase 4: Ingress-NGINX Decommissioning

Once 100% of production traffic flows through the Gateway API tier for 48 hours without regression:

1. Delete legacy Ingress resources across application namespaces.

2. Verify that no traffic targets the Ingress-NGINX controller pods via internal metrics.

3. Decommission the Ingress-NGINX controller deployment and release associated cloud resources.

---

Production Hardening & Systems Tuning

To maximize throughput and prevent socket buffer starvation on high-density nodes, apply the following Linux kernel parameters, Envoy runtime directives, and eBPF network configurations.

Linux Kernel Host Tuning (`/etc/sysctl.d/99-gateway-tuning.conf`)

High-volume ingress gateways handling 50,000+ persistent connections require expanded TCP socket buffers and elevated connection backlogs:

  # Maximum socket receive/send buffer sizes (16MB)
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216

  # Connection backlog queue depth
net.core.somaxconn = 65535
net.ipv4.tcp_max_syn_backlog = 65535

  # Local ephemeral port range expansion
net.ipv4.ip_local_port_range = 1024 65535

  # Fast recycling of TIME_WAIT sockets
net.ipv4.tcp_tw_reuse = 1

  # System file descriptor allocation
fs.file-max = 2097152

  # Disable TCP slow start after idle
net.ipv4.tcp_slow_start_after_idle = 0

Apply the changes immediately without restarting:

sudo sysctl -p /etc/sysctl.d/99-gateway-tuning.conf

Envoy Gateway Tuning via EnvoyProxy CRD

When deploying Envoy Gateway, tune concurrency, connection buffer limits, and upstream connection pooling via the EnvoyProxy resource:

apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: production-gateway-proxy-config
  namespace: infra-gateways
spec:
  concurrency: 16
  telemetry:
    metrics:
      prometheus:
        disableVirtualHostStats: false
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        replicas: 4
        resources:
          limits:
            cpu: "8"
            memory: "4Gi"
          requests:
            cpu: "4"
            memory: "2Gi"

Cilium eBPF Acceleration Configuration

To activate in-kernel socket splicing and bypass iptables connection tracking completely, deploy Cilium with host-routing and socket operations enabled:

  # Helm values for Cilium Gateway API deployment
gatewayAPI:
  enabled: true
kubeProxyReplacement: "true"
bpf:
  masquerade: true
  hostRouting: true
sockops:
  enabled: true
devices: "eth+"
loadBalancer:
  acceleration: native
  mode: dsr

---

Falsifiability & Post-Migration Verification ("How Would We Know This Failed?")

A production migration requires deterministic, falsifiable telemetry to confirm whether the deployment succeeded or failed. If any of the following criteria trigger, the migration must be marked as failed and routed back to legacy controllers.

Critical Failure Signatures and Thresholds

1. xDS Sync Rejection / Config Drift: If Envoy Gateway fails to parse or apply route objects transmitted via xDS, it rejects the configuration with a NACK.

Metric*: envoy_control_plane_rds_rejected_configs > 0 or envoy_control_plane_cds_rejected_configs > 0.

Verification Command*:

     kubectl exec -it deployment/envoy-gateway -n envoy-gateway-system -- \
       curl -s http://127.0.0.1:19000/stats | grep rejected_configs

Falsifiability Check*: If rejected_configs is greater than zero for more than 3 consecutive reconciliation periods, the Gateway API controller has failed schema synchronization.

2. Route Convergence SLA Breach: Route propagation from CRD application to active data-plane routing must execute in under 250 ms.

Metric*: gatewayapi_route_sync_duration_seconds{quantile="0.99"} > 0.250.

Falsifiability Check*: If canary weight adjustments take longer than 1 second to register in edge access logs, dynamic convergence has degraded.

3. eBPF Socket Map Saturation: Under sustained traffic, the Cilium sock_ops BPF map must maintain adequate headroom to prevent fallback to slower networking layers.

Metric*: cilium_bpf_map_pressure{map_name="cilium_sock_ops"} > 0.80.

Verification Command*:

     cilium bpf map get cilium_sock_ops | wc -l

Falsifiability Check*: If the map reaches full capacity (cilium_bpf_map_pressure >= 1.0 or exceeds the configured high-water threshold), new TCP connection registrations fail and fall back to the standard Linux TCP/IP network stack, producing measurable increases in kernel CPU consumption and packet processing latency.

4. Tail Latency SLA Violation: Under 50,000 RPS, the p99 latency must not exceed 12 ms during route modifications.

PromQL Rule*:

     histogram_quantile(0.99, sum(rate(http_request_duration_seconds_bucket{gateway="internal-edge-gateway"}[2m])) by (le)) > 0.012

Falsifiability Check*: If p99 latency exceeds 12 ms for longer than 60 seconds, worker connection exhaustion or route tree lock contention has occurred.

---

Frequently Asked Questions (FAQ)

How does the Kubernetes Gateway API handle automated TLS certificate management with Cert-Manager?

In Ingress-NGINX, certificate generation relied on annotations like cert-manager.io/cluster-issuer: "letsencrypt-prod". In Gateway API, Cert-Manager operates natively against the Gateway resource. The platform operator configures a listener on port 443 referencing a Secret in spec.listeners[*].tls.certificateRefs. Cert-Manager v1.12+ watches Gateway resources directly, detects missing secrets, and provisions ACME HTTP-01 or DNS-01 challenges without modifying developer-facing HTTPRoute manifests.

Can Ingress-NGINX and Gateway API controllers coexist in the same cluster during migration?

Yes. Both controllers can operate concurrently within the same Kubernetes cluster without port conflicts, provided they utilize separate cloud load balancers or distinct node ports. Legacy Ingress resources remain managed by Ingress-NGINX, while HTTPRoute resources attach to the GatewayClass. This separation allows teams to migrate individual microservices domain by domain or path by path.

When should an engineering team choose Envoy Gateway over Cilium Gateway API?

Envoy Gateway is ideal for organizations seeking a standalone, portable Layer-7 gateway that operates independently of the cluster CNI, supporting diverse cloud providers and hybrid Kubernetes environments without requiring kernel privileges. Cilium Gateway API is the optimal choice for organizations already utilizing Cilium as their CNI, or teams seeking maximum hardware throughput and lowest tail latency via eBPF kernel socket switching (sockops) and XDP bypass.

What is the memory footprint impact when scaling to more than 10,000 active HTTPRoute resources?

Ingress-NGINX memory consumption scales with both total route volume and the rate of configuration changes. Because each reload generates a complete new set of worker processes, memory usage multiplies during reloads as older worker generations drain connections alongside newly spawned processes. At high route volumes, this multi-generation overlap can substantially expand memory consumption during deployment surges. In contrast, Envoy Gateway maintains route trees in optimized radix tree (trie) structures via RDS. Updates are applied dynamically in place via atomic pointer swaps without spawning duplicate worker processes, maintaining a predictable, stable memory footprint during continuous updates.

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Sources

• Kubernetes Gateway API Specification & Guidelines
• Envoy Gateway Architecture & xDS Internals
• Cilium eBPF Host-Routing and Service Mesh Documentation
• Linux Kernel BPF sockops and Sockhash Map Documentation
• Kubernetes SIG-Network Ingress-to-Gateway API Migration Guidelines