Allow adding limits

Author: tallclair

Diff for: pkg/kubelet/kubelet_pods.go

@@ -1791,19 +1791,31 @@ func allocatedResourcesMatchStatus(allocatedPod *v1.Pod, podStatus *kubecontaine
 
 			// Only compare resizeable resources, and only compare resources that are explicitly configured.
 			if hasCPUReq {
-				// If both allocated & status CPU requests are at or below MinShares then they are considered equal.
-				if !cpuReq.Equal(*cs.Resources.CPURequest) &&
+				if cs.Resources.CPURequest == nil {
+					if !cpuReq.IsZero() {
+						return false
+					}
+				} else if !cpuReq.Equal(*cs.Resources.CPURequest) &&
 					(cpuReq.MilliValue() > cm.MinShares || cs.Resources.CPURequest.MilliValue() > cm.MinShares) {
+					// If both allocated & status CPU requests are at or below MinShares then they are considered equal.
 					return false
 				}
 			}
 			if hasCPULim {
-				if !cpuLim.Equal(*cs.Resources.CPULimit) {
+				if cs.Resources.CPULimit == nil {
+					if !cpuLim.IsZero() {
+						return false
+					}
+				} else if !cpuLim.Equal(*cs.Resources.CPULimit) {
 					return false
 				}
 			}
 			if hasMemLim {
-				if !memLim.Equal(*cs.Resources.MemoryLimit) {
+				if cs.Resources.MemoryLimit == nil {
+					if !memLim.IsZero() {
+						return false
+					}
+				} else if !memLim.Equal(*cs.Resources.MemoryLimit) {
 					return false
 				}
 			}

Diff for: pkg/kubelet/kubelet_pods_test.go

@@ -6797,6 +6797,38 @@ func TestAllocatedResourcesMatchStatus(t *testing.T) {
 			CPURequest: resource.NewMilliQuantity(2, resource.DecimalSI),
 		},
 		expectMatch: true,
+	}, {
+		name: "nil status resources: cpu request mismatch",
+		allocatedResources: v1.ResourceRequirements{
+			Requests: v1.ResourceList{
+				v1.ResourceCPU: resource.MustParse("100m"),
+			},
+		},
+		statusResources: &kubecontainer.ContainerResources{},
+		expectMatch:     false,
+	}, {
+		name: "nil status resources: cpu limit mismatch",
+		allocatedResources: v1.ResourceRequirements{
+			Requests: v1.ResourceList{
+				v1.ResourceCPU: resource.MustParse("100m"),
+			},
+			Limits: v1.ResourceList{
+				v1.ResourceCPU: resource.MustParse("100m"),
+			},
+		},
+		statusResources: &kubecontainer.ContainerResources{
+			CPURequest: resource.NewMilliQuantity(2, resource.DecimalSI),
+		},
+		expectMatch: false,
+	}, {
+		name: "nil status resources: memory limit mismatch",
+		allocatedResources: v1.ResourceRequirements{
+			Limits: v1.ResourceList{
+				v1.ResourceMemory: resource.MustParse("100M"),
+			},
+		},
+		statusResources: &kubecontainer.ContainerResources{},
+		expectMatch:     false,
 	}}
 
 	for _, test := range tests {

Diff for: pkg/kubelet/kuberuntime/kuberuntime_manager.go

@@ -584,8 +584,10 @@ func (m *kubeGenericRuntimeManager) computePodResizeAction(pod *v1.Pod, containe
 		cpuRequest:    container.Resources.Requests.Cpu().MilliValue(),
 	}
 
-	// Default current values to the desired values so that a resize isn't triggered for missing values.
-	currentResources := desiredResources
+	currentResources := containerResources{
+		// memoryRequest isn't set by the runtime, so default it to the desired.
+		memoryRequest: desiredResources.memoryRequest,
+	}
 	if kubeContainerStatus.Resources.MemoryLimit != nil {
 		currentResources.memoryLimit = kubeContainerStatus.Resources.MemoryLimit.Value()
 	}
@@ -839,16 +841,21 @@ func (m *kubeGenericRuntimeManager) updatePodContainerResources(pod *v1.Pod, res
 			}
 			switch resourceName {
 			case v1.ResourceMemory:
-				return status.Resources.MemoryLimit.Equal(*container.Resources.Limits.Memory())
+				actualLimit := nonNilQuantity(status.Resources.MemoryLimit)
+				return actualLimit.Equal(*container.Resources.Limits.Memory())
 			case v1.ResourceCPU:
-				if !status.Resources.CPULimit.Equal(*container.Resources.Limits.Cpu()) {
+				actualLimit := nonNilQuantity(status.Resources.CPULimit)
+				actualRequest := nonNilQuantity(status.Resources.CPURequest)
+				desiredLimit := container.Resources.Limits.Cpu()
+				desiredRequest := container.Resources.Requests.Cpu()
+				if !actualLimit.Equal(*desiredLimit) {
 					return false // limits don't match
-				} else if status.Resources.CPURequest.Equal(*container.Resources.Requests.Cpu()) {
+				} else if actualRequest.Equal(*desiredRequest) {
 					return true // requests & limits both match
 				}
 				// Consider requests equal if both are at or below MinShares.
-				return status.Resources.CPURequest.MilliValue() <= cm.MinShares &&
-					container.Resources.Requests.Cpu().MilliValue() <= cm.MinShares
+				return actualRequest.MilliValue() <= cm.MinShares &&
+					desiredRequest.MilliValue() <= cm.MinShares
 			default:
 				return true // Shouldn't happen.
 			}
@@ -870,6 +877,15 @@ func (m *kubeGenericRuntimeManager) updatePodContainerResources(pod *v1.Pod, res
 	return nil
 }
 
+// nonNilQuantity returns a non-nil quantity. If the input is non-nil, it is returned. Otherwise a
+// pointer to the zero value is returned.
+func nonNilQuantity(q *resource.Quantity) *resource.Quantity {
+	if q != nil {
+		return q
+	}
+	return &resource.Quantity{}
+}
+
 // computePodActions checks whether the pod spec has changed and returns the changes if true.
 func (m *kubeGenericRuntimeManager) computePodActions(ctx context.Context, pod *v1.Pod, podStatus *kubecontainer.PodStatus) podActions {
 	klog.V(5).InfoS("Syncing Pod", "pod", klog.KObj(pod))