OCPBUGS-13153: Limit the value of GOMAXPROCS on node-exporter.

xxxxx

Signed-off-by: Ayoub Mrini <amrini@redhat.com>

assets/node-exporter/daemonset.yaml

@@ -41,6 +41,7 @@ spec:
         - --collector.cpu.info
         - --collector.textfile.directory=/var/node_exporter/textfile
         - --no-collector.btrfs
+        command: ["/bin/bash", "/entryponit"]
         image: quay.io/prometheus/node-exporter:v1.5.0
         name: node-exporter
         resources:
@@ -61,6 +62,9 @@ spec:
         - mountPath: /var/node_exporter/textfile
           name: node-exporter-textfile
           readOnly: true
+        - mountPath: /entryponit
+          name: node-exporter-entrypoint
+          readOnly: true
         workingDir: /var/node_exporter/textfile
       - args:
         - --logtostderr
@@ -164,6 +168,9 @@ spec:
       - name: node-exporter-kube-rbac-proxy-config
         secret:
           secretName: node-exporter-kube-rbac-proxy-config
+      - configMap:
+          name: node-exporter-entrypoint
+        name: node-exporter-entrypoint
   updateStrategy:
     rollingUpdate:
       maxUnavailable: 10%

assets/node-exporter/entrypoint.yaml

@@ -0,0 +1,20 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: node-exporter-entrypoint
+  namespace: openshift-monitoring
+data:
+  entrypoint: |
+    export GOMAXPROCS=4
+
+    # no affinity even when cpusets is set as requests is not integer
+    NUM_CPUS=$(grep -c '^processor' "/proc/cpuinfo" 2>/dev/null || echo "0")
+
+    if [ "$NUM_CPUS" -lt "$GOMAXPROCS" ]; then
+      export GOMAXPROCS="$NUM_CPUS"
+    fi
+
+    echo "Set GOMAXPROCS=$GOMAXPROCS"
+
+    # TODO: maybe get /bin/node_exporter somewhere? envvar?
+    exec /bin/node_exporter "$@"