kubelet(OOM-score-adj): change OOM score adjustment calculation for sidecar container

pkg/kubelet/qos/helpers.go

@@ -0,0 +1,43 @@
+/*
+Copyright 2024 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 qos contains helper functions for quality of service.
+// For each resource (memory, CPU) Kubelet supports three classes of containers.
+// Memory guaranteed containers will receive the highest priority and will get all the resources
+// they need.
+// Burstable containers will be guaranteed their request and can "burst" and use more resources
+// when available.
+// Best-Effort containers, which don't specify a request, can use resources only if not being used
+// by other pods.
+
+package qos // import "k8s.io/kubernetes/pkg/kubelet/qos"
+
+import (
+	v1 "k8s.io/api/core/v1"
+)
+
+// minRegularContainerMemory returns the minimum memory resource quantity
+// across all regular containers in pod.Spec.Containers.
+// It does not include initContainers (both restartable and non-restartable).
+func minRegularContainerMemory(pod v1.Pod) int64 {
+	memoryValue := pod.Spec.Containers[0].Resources.Requests.Memory().Value()
+	for _, container := range pod.Spec.Containers[1:] {
+		if container.Resources.Requests.Memory().Value() < memoryValue {
+			memoryValue = container.Resources.Requests.Memory().Value()
+		}
+	}
+	return memoryValue
+}