fix linting issues

Author: ttetyanka

cluster-autoscaler/core/scaledown/latencytracker/node_latency_tracker.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2019 The Kubernetes 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 latencytracker
 
 import (
@@ -8,25 +24,31 @@ import (
 	"k8s.io/klog/v2"
 )
 
+// LatencyTracker defines the interface for tracking node removal latency.
+// Implementations record when nodes become unneeded, observe deletion events,
+// and expose thresholds for measuring node removal duration.
 type LatencyTracker interface {
 	ObserveDeletion(nodeName string, timestamp time.Time)
 	UpdateStateWithUnneededList(list []*apiv1.Node, currentlyInDeletion map[string]bool, timestamp time.Time)
 	UpdateThreshold(nodeName string, threshold time.Duration)
 	GetTrackedNodes() []string
 }
-type NodeInfo struct {
+type nodeInfo struct {
 	UnneededSince time.Time
 	Threshold     time.Duration
 }
 
+// NodeLatencyTracker is a concrete implementation of LatencyTracker.
+// It keeps track of nodes that are marked as unneeded, when they became unneeded,
+// and thresholds to adjust node removal latency metrics.
 type NodeLatencyTracker struct {
-	nodes map[string]NodeInfo
+	nodes map[string]nodeInfo
 }
 
 // NewNodeLatencyTracker creates a new tracker.
 func NewNodeLatencyTracker() *NodeLatencyTracker {
 	return &NodeLatencyTracker{
-		nodes: make(map[string]NodeInfo),
+		nodes: make(map[string]nodeInfo),
 	}
 }
 
@@ -41,7 +63,7 @@ func (t *NodeLatencyTracker) UpdateStateWithUnneededList(
 		currentSet[node.Name] = struct{}{}
 
 		if _, exists := t.nodes[node.Name]; !exists {
-			t.nodes[node.Name] = NodeInfo{
+			t.nodes[node.Name] = nodeInfo{
 				UnneededSince: timestamp,
 				Threshold:     0,
 			}

cluster-autoscaler/core/scaledown/latencytracker/node_latency_tracker_test.go

@@ -1,14 +1,14 @@
 /*
-Copyright 2024 The Kubernetes Authors.
+Copyright 2019 The Kubernetes 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,
+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.
@@ -29,7 +29,7 @@ func TestNodeLatencyTracker(t *testing.T) {
 
 	tests := []struct {
 		name                  string
-		setupNodes            map[string]NodeInfo
+		setupNodes            map[string]nodeInfo
 		unneededList          []string
 		currentlyInDeletion   map[string]bool
 		updateThresholds      map[string]time.Duration
@@ -39,7 +39,7 @@ func TestNodeLatencyTracker(t *testing.T) {
 	}{
 		{
 			name:                 "add new unneeded nodes",
-			setupNodes:           map[string]NodeInfo{},
+			setupNodes:           map[string]nodeInfo{},
 			unneededList:         []string{"node1", "node2"},
 			currentlyInDeletion:  map[string]bool{},
 			updateThresholds:     map[string]time.Duration{},
@@ -48,7 +48,7 @@ func TestNodeLatencyTracker(t *testing.T) {
 		},
 		{
 			name: "observe deletion with threshold",
-			setupNodes: map[string]NodeInfo{
+			setupNodes: map[string]nodeInfo{
 				"node1": {UnneededSince: baseTime, Threshold: 2 * time.Second},
 			},
 			unneededList:         []string{},
@@ -62,7 +62,7 @@ func TestNodeLatencyTracker(t *testing.T) {
 		},
 		{
 			name: "remove unneeded node not in deletion",
-			setupNodes: map[string]NodeInfo{
+			setupNodes: map[string]nodeInfo{
 				"node1": {UnneededSince: baseTime, Threshold: 1 * time.Second},
 				"node2": {UnneededSince: baseTime, Threshold: 0},
 			},
@@ -77,7 +77,7 @@ func TestNodeLatencyTracker(t *testing.T) {
 		},
 		{
 			name: "update threshold",
-			setupNodes: map[string]NodeInfo{
+			setupNodes: map[string]nodeInfo{
 				"node1": {UnneededSince: baseTime, Threshold: 1 * time.Second},
 			},
 			unneededList:        []string{"node1"},

cluster-autoscaler/metrics/metrics.go

@@ -761,6 +761,8 @@ func ObserveBinpackingHeterogeneity(instanceType, cpuCount, namespaceCount strin
 	binpackingHeterogeneity.WithLabelValues(instanceType, cpuCount, namespaceCount).Observe(float64(pegCount))
 }
 
+// UpdateScaleDownNodeDeletionDuration records the time after which node was deleted/needed
+// again after being marked unneded
 func UpdateScaleDownNodeDeletionDuration(deleted string, duration time.Duration) {
 	scaleDownNodeDeletionDuration.WithLabelValues(deleted).Observe(duration.Seconds())
 }