From 6c77c01f243aa7be9e6d7d52b120a5dbff9921da Mon Sep 17 00:00:00 2001
From: Wojciech Tyczynski <wojtekt@google.com>
Date: Thu, 7 Jul 2016 13:46:46 +0200
Subject: [PATCH] Avoid copying nodes in priority functions

---
 .../algorithm/priorities/node_affinity.go       |  3 ++-
 .../algorithm/priorities/priorities.go          | 17 +++++++++++------
 .../algorithm/priorities/taint_toleration.go    |  3 ++-
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/plugin/pkg/scheduler/algorithm/priorities/node_affinity.go b/plugin/pkg/scheduler/algorithm/priorities/node_affinity.go
index abe064a301..5f3043fb5b 100644
--- a/plugin/pkg/scheduler/algorithm/priorities/node_affinity.go
+++ b/plugin/pkg/scheduler/algorithm/priorities/node_affinity.go
@@ -83,7 +83,8 @@ func (s *NodeAffinity) CalculateNodeAffinityPriority(pod *api.Pod, nodeNameToInf
 	}
 
 	result := []schedulerapi.HostPriority{}
-	for _, node := range nodes.Items {
+	for i := range nodes.Items {
+		node := &nodes.Items[i]
 		fScore := float64(0)
 		if maxCount > 0 {
 			fScore = 10 * (float64(counts[node.Name]) / float64(maxCount))
diff --git a/plugin/pkg/scheduler/algorithm/priorities/priorities.go b/plugin/pkg/scheduler/algorithm/priorities/priorities.go
index d761ce96fd..bebb299b07 100644
--- a/plugin/pkg/scheduler/algorithm/priorities/priorities.go
+++ b/plugin/pkg/scheduler/algorithm/priorities/priorities.go
@@ -44,7 +44,8 @@ func calculateScore(requested int64, capacity int64, node string) int {
 
 // Calculate the resource occupancy on a node.  'node' has information about the resources on the node.
 // 'pods' is a list of pods currently scheduled on the node.
-func calculateResourceOccupancy(pod *api.Pod, node api.Node, nodeInfo *schedulercache.NodeInfo) schedulerapi.HostPriority {
+// TODO: Use Node() from nodeInfo instead of passing it.
+func calculateResourceOccupancy(pod *api.Pod, node *api.Node, nodeInfo *schedulercache.NodeInfo) schedulerapi.HostPriority {
 	totalMilliCPU := nodeInfo.NonZeroRequest().MilliCPU
 	totalMemory := nodeInfo.NonZeroRequest().Memory
 	capacityMilliCPU := node.Status.Allocatable.Cpu().MilliValue()
@@ -85,7 +86,8 @@ func LeastRequestedPriority(pod *api.Pod, nodeNameToInfo map[string]*schedulerca
 	}
 
 	list := schedulerapi.HostPriorityList{}
-	for _, node := range nodes.Items {
+	for i := range nodes.Items {
+		node := &nodes.Items[i]
 		list = append(list, calculateResourceOccupancy(pod, node, nodeNameToInfo[node.Name]))
 	}
 	return list, nil
@@ -155,7 +157,8 @@ func ImageLocalityPriority(pod *api.Pod, nodeNameToInfo map[string]*schedulercac
 	}
 
 	for _, container := range pod.Spec.Containers {
-		for _, node := range nodes.Items {
+		for i := range nodes.Items {
+			node := &nodes.Items[i]
 			// Check if this container's image is present and get its size.
 			imageSize := checkContainerImageOnNode(node, container)
 			// Add this size to the total result of this node.
@@ -174,7 +177,7 @@ func ImageLocalityPriority(pod *api.Pod, nodeNameToInfo map[string]*schedulercac
 }
 
 // checkContainerImageOnNode checks if a container image is present on a node and returns its size.
-func checkContainerImageOnNode(node api.Node, container api.Container) int64 {
+func checkContainerImageOnNode(node *api.Node, container api.Container) int64 {
 	for _, image := range node.Status.Images {
 		for _, name := range image.Names {
 			if container.Image == name {
@@ -219,13 +222,15 @@ func BalancedResourceAllocation(pod *api.Pod, nodeNameToInfo map[string]*schedul
 	}
 
 	list := schedulerapi.HostPriorityList{}
-	for _, node := range nodes.Items {
+	for i := range nodes.Items {
+		node := &nodes.Items[i]
 		list = append(list, calculateBalancedResourceAllocation(pod, node, nodeNameToInfo[node.Name]))
 	}
 	return list, nil
 }
 
-func calculateBalancedResourceAllocation(pod *api.Pod, node api.Node, nodeInfo *schedulercache.NodeInfo) schedulerapi.HostPriority {
+// TODO: Use Node() from nodeInfo instead of passing it.
+func calculateBalancedResourceAllocation(pod *api.Pod, node *api.Node, nodeInfo *schedulercache.NodeInfo) schedulerapi.HostPriority {
 	totalMilliCPU := nodeInfo.NonZeroRequest().MilliCPU
 	totalMemory := nodeInfo.NonZeroRequest().Memory
 	score := int(0)
diff --git a/plugin/pkg/scheduler/algorithm/priorities/taint_toleration.go b/plugin/pkg/scheduler/algorithm/priorities/taint_toleration.go
index 3ea7f10f6d..2876fc097d 100644
--- a/plugin/pkg/scheduler/algorithm/priorities/taint_toleration.go
+++ b/plugin/pkg/scheduler/algorithm/priorities/taint_toleration.go
@@ -83,7 +83,8 @@ func (s *TaintToleration) ComputeTaintTolerationPriority(pod *api.Pod, nodeNameT
 	tolerationList := getAllTolerationPreferNoSchedule(tolerations)
 
 	// calculate the intolerable taints for all the nodes
-	for _, node := range nodes.Items {
+	for i := range nodes.Items {
+		node := &nodes.Items[i]
 		taints, err := api.GetTaintsFromNodeAnnotations(node.Annotations)
 		if err != nil {
 			return nil, err