fix: add missing metric descriptors to Describe() in vGPUmonitor

cmd/vGPUmonitor/metrics.go

@@ -211,16 +211,17 @@ func sendLegacyMetric(ch chan<- prometheus.Metric, desc *prometheus.Desc, valueT
 	}
 }
 
-// Describe is implemented with DescribeByCollect. That's possible because the
-// Collect method will always return the same two metrics with the same two
-// descriptors.
+// Describe sends all the metrics descriptors that the collector might use.
+// These descriptors are used by the Prometheus registry to register the metrics.
 func (cc ClusterManagerCollector) Describe(ch chan<- *prometheus.Desc) {
 	ch <- hostGPUdesc
 	ch <- ctrvGPUdesc
 	ch <- ctrvGPUlimitdesc
 	ch <- hostGPUUtilizationdesc
 	ch <- ctrDeviceMemorydesc
 	ch <- ctrDeviceUtilizationdesc
+	ch <- ctrDeviceLastKernelDesc
+	ch <- ctrDeviceMigInfo
 	ch <- ctrDeviceMemoryContextDesc
 	ch <- ctrDeviceMemoryModuleDesc
 	ch <- ctrDeviceMemoryBufferDesc

cmd/vGPUmonitor/metrics_test.go

@@ -0,0 +1,70 @@
+/*
+Copyright 2024 The HAMi Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"k8s.io/client-go/informers"
+	"k8s.io/client-go/kubernetes/fake"
+
+	"github.com/Project-HAMi/HAMi/pkg/monitor/nvidia"
+	"github.com/Project-HAMi/HAMi/pkg/util"
+)
+
+func TestDescribeCollectSync(t *testing.T) {
+	reg := prometheus.NewPedanticRegistry()
+
+	t.Setenv(util.NodeNameEnvName, "test-node")
+	client := fake.NewSimpleClientset()
+	informerFactory := informers.NewSharedInformerFactory(client, 0)
+	podLister := informerFactory.Core().V1().Pods().Lister()
+
+	c := &ClusterManager{
+		Zone:            "test-zone",
+		LegacyMetrics:   false,
+		PodLister:       podLister,
+		containerLister: &nvidia.ContainerLister{},
+	}
+	cc := ClusterManagerCollector{ClusterManager: c}
+
+	if err := reg.Register(cc); err != nil {
+		t.Fatalf("Failed to register ClusterManagerCollector (non-legacy): %v", err)
+	}
+
+	if _, err := reg.Gather(); err != nil {
+		t.Errorf("Gather failed (non-legacy): %v", err)
+	}
+
+	regLegacy := prometheus.NewPedanticRegistry()
+	cLegacy := &ClusterManager{
+		Zone:            "test-zone-legacy",
+		LegacyMetrics:   true,
+		PodLister:       podLister,
+		containerLister: &nvidia.ContainerLister{},
+	}
+	initLegacyDescriptors()
+	ccLegacy := ClusterManagerCollector{ClusterManager: cLegacy}
+
+	if err := regLegacy.Register(ccLegacy); err != nil {
+		t.Fatalf("Failed to register ClusterManagerCollector (legacy): %v", err)
+	}
+	if _, err := regLegacy.Gather(); err != nil {
+		t.Errorf("Gather failed (legacy): %v", err)
+	}
+}