Rate limit garbage collection inside ClusterState

vertical-pod-autoscaler/pkg/recommender/checkpoint/checkpoint_writer_test.go

@@ -42,6 +42,8 @@ var (
 	}
 )
 
+const testGcPeriod = time.Minute
+
 func addVpa(t *testing.T, cluster *model.ClusterState, vpaID model.VpaID, selector string) *model.Vpa {
 	var apiObject vpa_types.VerticalPodAutoscaler
 	apiObject.Namespace = vpaID.Namespace
@@ -56,7 +58,7 @@ func addVpa(t *testing.T, cluster *model.ClusterState, vpaID model.VpaID, select
 }
 
 func TestMergeContainerStateForCheckpointDropsRecentMemoryPeak(t *testing.T) {
-	cluster := model.NewClusterState()
+	cluster := model.NewClusterState(testGcPeriod)
 	cluster.AddOrUpdatePod(testPodID1, testLabels, v1.PodRunning)
 	assert.NoError(t, cluster.AddOrUpdateContainer(testContainerID1, testRequest))
 	container := cluster.GetContainer(testContainerID1)

vertical-pod-autoscaler/pkg/recommender/input/cluster_feeder_test.go

@@ -19,6 +19,7 @@ package input
 import (
 	"fmt"
 	"testing"
+	"time"
 
 	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/assert"
@@ -60,11 +61,12 @@ var (
 )
 
 const (
-	kind       = "dodokind"
-	name1      = "dotaro"
-	name2      = "doseph"
-	namespace  = "testNamespace"
-	apiVersion = "stardust"
+	kind         = "dodokind"
+	name1        = "dotaro"
+	name2        = "doseph"
+	namespace    = "testNamespace"
+	apiVersion   = "stardust"
+	testGcPeriod = time.Minute
 )
 
 func TestLoadPods(t *testing.T) {
@@ -206,7 +208,7 @@ func TestLoadPods(t *testing.T) {
 
 			targetSelectorFetcher := target_mock.NewMockVpaTargetSelectorFetcher(ctrl)
 
-			clusterState := model.NewClusterState()
+			clusterState := model.NewClusterState(testGcPeriod)
 
 			clusterStateFeeder := clusterStateFeeder{
 				vpaLister:       vpaLister,
@@ -321,7 +323,7 @@ func TestClusterStateFeeder_LoadPods(t *testing.T) {
 		},
 	} {
 		t.Run(tc.Name, func(t *testing.T) {
-			clusterState := model.NewClusterState()
+			clusterState := model.NewClusterState(testGcPeriod)
 			for i, selector := range tc.VPALabelSelectors {
 				vpaLabel, err := labels.Parse(selector)
 				assert.NoError(t, err)

vertical-pod-autoscaler/pkg/recommender/model/aggregate_container_state_test.go

@@ -72,7 +72,7 @@ func addTestMemorySample(cluster *ClusterState, container ContainerID, memoryByt
 // container CPU and memory peak histograms, grouping the two containers
 // with the same name ('app-A') together.
 func TestAggregateStateByContainerName(t *testing.T) {
-	cluster := NewClusterState()
+	cluster := NewClusterState(testGcPeriod)
 	cluster.AddOrUpdatePod(testPodID1, testLabels, apiv1.PodRunning)
 	otherLabels := labels.Set{"label-2": "value-2"}
 	cluster.AddOrUpdatePod(testPodID2, otherLabels, apiv1.PodRunning)

vertical-pod-autoscaler/pkg/recommender/model/cluster.go

@@ -54,6 +54,9 @@ type ClusterState struct {
 	// Map with all label sets used by the aggregations. It serves as a cache
 	// that allows to quickly access labels.Set corresponding to a labelSetKey.
 	labelSetMap labelSetMap
+
+	lastAggregateContainerStateGC time.Time
+	gcInterval                    time.Duration
 }
 
 // StateMapSize is the number of pods being tracked by the VPA
@@ -92,13 +95,15 @@ type PodState struct {
 }
 
 // NewClusterState returns a new ClusterState with no pods.
-func NewClusterState() *ClusterState {
+func NewClusterState(gcInterval time.Duration) *ClusterState {
 	return &ClusterState{
-		Pods:              make(map[PodID]*PodState),
-		Vpas:              make(map[VpaID]*Vpa),
-		EmptyVPAs:         make(map[VpaID]time.Time),
-		aggregateStateMap: make(aggregateContainerStatesMap),
-		labelSetMap:       make(labelSetMap),
+		Pods:                          make(map[PodID]*PodState),
+		Vpas:                          make(map[VpaID]*Vpa),
+		EmptyVPAs:                     make(map[VpaID]time.Time),
+		aggregateStateMap:             make(aggregateContainerStatesMap),
+		labelSetMap:                   make(labelSetMap),
+		lastAggregateContainerStateGC: time.Unix(0, 0),
+		gcInterval:                    gcInterval,
 	}
 }
 
@@ -343,12 +348,7 @@ func (cluster *ClusterState) findOrCreateAggregateContainerState(containerID Con
 	return aggregateContainerState
 }
 
-// GarbageCollectAggregateCollectionStates removes obsolete AggregateCollectionStates from the ClusterState.
-// AggregateCollectionState is obsolete in following situations:
-// 1) It has no samples and there are no more active pods that can contribute,
-// 2) The last sample is too old to give meaningful recommendation (>8 days),
-// 3) There are no samples and the aggregate state was created >8 days ago.
-func (cluster *ClusterState) GarbageCollectAggregateCollectionStates(now time.Time) {
+func (cluster *ClusterState) garbageCollectAggregateCollectionStates(now time.Time) {
 	klog.V(1).Info("Garbage collection of AggregateCollectionStates triggered")
 	keysToDelete := make([]AggregateStateKey, 0)
 	activeKeys := cluster.getActiveAggregateStateKeys()
@@ -372,6 +372,20 @@ func (cluster *ClusterState) GarbageCollectAggregateCollectionStates(now time.Ti
 	}
 }
 
+// RateLimitedGarbageCollectAggregateCollectionStates removes obsolete AggregateCollectionStates from the ClusterState.
+// It performs clean up only if more than `gcInterval` passed since the last time it performed a clean up.
+// AggregateCollectionState is obsolete in following situations:
+// 1) It has no samples and there are no more active pods that can contribute,
+// 2) The last sample is too old to give meaningful recommendation (>8 days),
+// 3) There are no samples and the aggregate state was created >8 days ago.
+func (cluster *ClusterState) RateLimitedGarbageCollectAggregateCollectionStates(now time.Time) {
+	if now.Sub(cluster.lastAggregateContainerStateGC) < cluster.gcInterval {
+		return
+	}
+	cluster.garbageCollectAggregateCollectionStates(now)
+	cluster.lastAggregateContainerStateGC = now
+}
+
 func (cluster *ClusterState) getActiveAggregateStateKeys() map[AggregateStateKey]bool {
 	activeKeys := map[AggregateStateKey]bool{}
 	for _, pod := range cluster.Pods {