feat(helm): add configurable relabelings to PodMonitor resources

charts/linkerd-control-plane/debug.values.yaml

@@ -0,0 +1,174 @@
+# =============================================================================
+# Linkerd Control Plane Chart - Debug Values
+# =============================================================================
+# This file contains test configurations for debugging and validating
+#
+# Usage:
+#   helm template . -f debug.values.yaml
+# =============================================================================
+
+# -----------------------------------------------------------------------------
+# Required Identity Configuration (Minimal for testing)
+# -----------------------------------------------------------------------------
+identityTrustAnchorsPEM: |
+  -----BEGIN CERTIFICATE-----
+  MIIB8TCCAZegAwIBAgIUHj2...
+  [test certificate]
+  -----END CERTIFICATE-----
+
+identity:
+  issuer:
+    tls:
+      crtPEM: |
+        -----BEGIN CERTIFICATE-----
+        MIIB8TCCAZegAwIBAgIUHj2...
+        [test certificate]
+        -----END CERTIFICATE-----
+      keyPEM: |
+        -----BEGIN PRIVATE KEY-----
+        MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQg...
+        [test private key]
+        -----END PRIVATE KEY-----
+
+# -----------------------------------------------------------------------------
+# Basic Chart Configuration
+# -----------------------------------------------------------------------------
+controllerReplicas: 1
+controllerLogLevel: "debug"
+controllerLogFormat: "json"
+
+# Enable debug features
+enablePprof: true
+enablePodDisruptionBudget: true
+
+# -----------------------------------------------------------------------------
+# PodMonitor Configuration - Main Feature Testing
+# -----------------------------------------------------------------------------
+podMonitor:
+  # Enable PodMonitor creation
+  enabled: true
+
+  # Global PodMonitor settings
+  scrapeInterval: "15s"
+  scrapeTimeout: "10s"
+  labels:
+    environment: "debug"
+    team: "platform"
+
+  # -----------------------------------------------------------------------------
+  # Controller PodMonitor Configuration
+  # -----------------------------------------------------------------------------
+  controller:
+    enabled: true
+
+    # Test metricRelabelings for controller
+    metricRelabelings:
+      # Drop high cardinality histogram buckets
+      - sourceLabels: [__name__]
+        regex: 'controller_.*_duration_seconds_bucket'
+        action: drop
+      # Drop specific controller metrics
+      - sourceLabels: [__name__]
+        regex: 'controller_k8s_api_.*_latency_.*'
+        action: drop
+      # Rename metrics
+
+    # Test additionalRelabelings for controller
+    additionalRelabelings:
+      # Add environment labels
+      - sourceLabels: [__meta_kubernetes_pod_label_environment]
+        targetLabel: environment
+        action: replace
+      # Drop unwanted labels
+      - action: labeldrop
+        regex: 'pod_template_hash|controller_revision_hash'
+      # Add version information
+
+
+  # -----------------------------------------------------------------------------
+  # Service Mirror PodMonitor Configuration
+  # -----------------------------------------------------------------------------
+  serviceMirror:
+    enabled: true
+
+    # Test metricRelabelings for service mirror
+    metricRelabelings:
+      # Drop error metrics for testing
+      - sourceLabels: [__name__]
+        regex: 'service_mirror_.*_errors_total'
+        action: drop
+      # Drop verbose connection metrics
+      - sourceLabels: [__name__]
+        regex: 'service_mirror_connection_.*_histogram'
+        action: drop
+
+    # Test additionalRelabelings for service mirror
+    additionalRelabelings:
+      # Add source cluster information
+      - sourceLabels: [__meta_kubernetes_pod_label_source_cluster]
+        targetLabel: source_cluster
+        action: replace
+      # Add destination cluster
+      - sourceLabels: [__meta_kubernetes_pod_label_dest_cluster]
+        targetLabel: dest_cluster
+        action: replace
+
+  # -----------------------------------------------------------------------------
+  # Proxy PodMonitor Configuration (Most Important)
+  # -----------------------------------------------------------------------------
+  proxy:
+    enabled: true
+
+    # Test metricRelabelings for proxy (cardinality control)
+    metricRelabelings:
+      # Drop high cardinality histogram buckets (production optimization)
+      - sourceLabels: [le]
+        regex: '2\.[0-9]+|3\.[0-9]+|4\.[0-9]+|5\.[0-9]+'
+        action: drop
+
+      # Drop verbose TCP metrics that cause high cardinality
+      - sourceLabels: [__name__]
+        regex: 'tcp_(read|write)_bytes_total|tcp_connection_.*'
+        action: drop
+
+    # Test additionalRelabelings for proxy
+    additionalRelabelings:
+      # Clean up temporary labels
+      - action: labeldrop
+        regex: '__tmp_.*'
+
+      # Add deployment information
+      - sourceLabels: [__meta_kubernetes_pod_label_pod_template_hash]
+        targetLabel: deployment_generation
+        action: replace
+
+# -----------------------------------------------------------------------------
+# Test Resource Configurations
+# -----------------------------------------------------------------------------
+proxy:
+  logLevel: "debug"
+  logFormat: "json"
+  resources:
+    cpu:
+      request: "50m"
+      limit: "100m"
+    memory:
+      request: "64Mi"
+      limit: "128Mi"
+
+# Controller resources for testing
+destinationResources:
+  cpu:
+    request: "50m"
+    limit: "100m"
+  memory:
+    request: "64Mi"
+    limit: "128Mi"
+
+identityResources:
+  cpu:
+    request: "25m"
+    limit: "50m"
+  memory:
+    request: "32Mi"
+    limit: "64Mi"

charts/linkerd-control-plane/templates/podmonitor.yaml

@@ -22,6 +22,10 @@ spec:
   podMetricsEndpoints:
     - interval: {{ $podMonitor.scrapeInterval }}
       scrapeTimeout: {{ $podMonitor.scrapeTimeout }}
+      {{- with $podMonitor.controller.metricRelabelings }}
+      metricRelabelings:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
       relabelings:
         - sourceLabels:
             - __meta_kubernetes_pod_container_port_name
@@ -35,6 +39,10 @@ spec:
             - __meta_kubernetes_pod_container_name
           action: replace
           targetLabel: component
+      {{- with $podMonitor.controller.additionalRelabelings }}
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+
 {{- end }}
 {{- if and $podMonitor.enabled $podMonitor.serviceMirror.enabled }}
 ---
@@ -60,6 +68,10 @@ spec:
   podMetricsEndpoints:
     - interval: {{ $podMonitor.scrapeInterval }}
       scrapeTimeout: {{ $podMonitor.scrapeTimeout }}
+      {{- with $podMonitor.serviceMirror.metricRelabelings }}
+      metricRelabelings:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
       relabelings:
         - sourceLabels:
             - __meta_kubernetes_pod_label_linkerd_io_control_plane_component
@@ -74,6 +86,9 @@ spec:
             - __meta_kubernetes_pod_container_name
           action: replace
           targetLabel: component
+      {{- with $podMonitor.serviceMirror.additionalRelabelings }}
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
 {{- end }}
 {{- if and $podMonitor.enabled $podMonitor.proxy.enabled }}
 ---
@@ -99,6 +114,10 @@ spec:
   podMetricsEndpoints:
     - interval: {{ $podMonitor.scrapeInterval }}
       scrapeTimeout: {{ $podMonitor.scrapeTimeout }}
+      {{- with $podMonitor.proxy.metricRelabelings }}
+      metricRelabelings:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
       relabelings:
         - sourceLabels:
             - __meta_kubernetes_pod_container_name
@@ -133,4 +152,7 @@ spec:
           regex: __tmp_pod_label_linkerd_io_(.+)
         - action: labelmap
           regex: __tmp_pod_label_(.+)
+      {{- with $podMonitor.proxy.additionalRelabelings }}
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
 {{- end }}

charts/linkerd-control-plane/values.yaml

@@ -732,14 +732,44 @@ podMonitor:
       matchNames:
         - {{ .Release.Namespace }}
         - linkerd-viz
+
+    # -- Custom metric relabelings for controller metrics
+    metricRelabelings: []
+    # Example:
+    # metricRelabelings:
+    #   - sourceLabels: [__name__]
+    #     regex: 'controller_.*_duration_seconds_bucket'
+    #     action: drop
+
+    # -- Additional relabelings appended to default ones
+    additionalRelabelings: []
+    # Example:
+    # additionalRelabelings:
+    #   - action: labeldrop
+    #     regex: 'unwanted_label'
+    #   - sourceLabels: [__meta_kubernetes_pod_label_version]
+    #     targetLabel: app_version
+    #     action: replace
+
   serviceMirror:
     # -- Enables the creation of PodMonitor for the Service Mirror component
     enabled: true
+
+    # -- Custom metric relabelings for service mirror metrics
+    metricRelabelings: []
+
+    # -- Additional relabelings appended to default ones
+    additionalRelabelings: []
+
   proxy:
     # -- Enables the creation of PodMonitor for the data-plane
     enabled: true
 
+    # -- Custom metric relabelings for proxy metrics (recommended for cardinality control)
+    metricRelabelings: []
 
+    # -- Additional relabelings appended to default ones
+    additionalRelabelings: []
 # Egress related configuration
 egress:
   # -- The namespace that is used to store egress configuration that affects all client workloads in the cluster