Add cpu and memory constraints to a Pod template

Add VM cpu and memory constraints to a Pod template for scheduling considerations. Signed-off-by: Vladik Romanovsky <[email protected]>
Ethan-2017 · Feb 26, 2018 · 86978cb · 86978cb
1 parent 56b2393
commit 86978cb
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Showing 3 changed files with 71 additions and 1 deletion.
diff --git a/pkg/api/v1/schema.go b/pkg/api/v1/schema.go
@@ -70,7 +70,7 @@ type ResourceRequirements struct {
 	// +optional
 	Requests v1.ResourceList `json:"requests,omitempty"`
 	// Limits describes the maximum amount of compute resources allowed.
-	// Valid resource keys are "cpu".
+	// Valid resource keys are "memory" and "cpu".
 	// +optional
 	Limits v1.ResourceList `json:"limits,omitempty"`
 }

diff --git a/pkg/virt-controller/services/template.go b/pkg/virt-controller/services/template.go
@@ -97,6 +97,12 @@ func (t *templateService) RenderLaunchManifest(vm *v1.VirtualMachine) (*kubev1.P
 	gracePeriodSeconds = gracePeriodSeconds + int64(15)
 	gracePeriodKillAfter := gracePeriodSeconds + int64(15)
 
+	// Consider CPU and memory requests and limits for pod scheduling
+	resources := kubev1.ResourceRequirements{}
+	vmResources := vm.Spec.Domain.Resources
+	resources.Requests = vmResources.Requests
+	resources.Limits = vmResources.Limits
+
 	// VM target container
 	container := kubev1.Container{
 		Name:            "compute",
@@ -132,6 +138,7 @@ func (t *templateService) RenderLaunchManifest(vm *v1.VirtualMachine) (*kubev1.P
 			SuccessThreshold:    int32(successThreshold),
 			FailureThreshold:    int32(failureThreshold),
 		},
+		Resources: resources,
 	}
 
 	containers, err := registrydisk.GenerateContainers(vm, "libvirt-runtime", "/var/run/libvirt")

diff --git a/pkg/virt-controller/services/template_test.go b/pkg/virt-controller/services/template_test.go
@@ -25,6 +25,7 @@ import (
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
 	kubev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	"kubevirt.io/kubevirt/pkg/api/v1"
@@ -123,6 +124,68 @@ var _ = Describe("Template", func() {
 				Expect(pod.Spec.Affinity).To(BeNil())
 			})
 		})
+		Context("with cpu and memory constraints", func() {
+			It("should add cpu and memory constraints to a template", func() {
+
+				vm := v1.VirtualMachine{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "testvm",
+						Namespace: "default",
+						UID:       "1234",
+					},
+					Spec: v1.VirtualMachineSpec{
+						Domain: v1.DomainSpec{
+							Resources: v1.ResourceRequirements{
+								Requests: kubev1.ResourceList{
+									kubev1.ResourceCPU:    resource.MustParse("1m"),
+									kubev1.ResourceMemory: resource.MustParse("1Gi"),
+								},
+								Limits: kubev1.ResourceList{
+									kubev1.ResourceCPU:    resource.MustParse("2m"),
+									kubev1.ResourceMemory: resource.MustParse("2Gi"),
+								},
+							},
+						},
+					},
+				}
+
+				pod, err := svc.RenderLaunchManifest(&vm)
+
+				Expect(err).To(BeNil())
+				Expect(pod.Spec.Containers[0].Resources.Requests.Cpu().String()).To(Equal("1m"))
+				Expect(pod.Spec.Containers[0].Resources.Limits.Cpu().String()).To(Equal("2m"))
+				Expect(pod.Spec.Containers[0].Resources.Requests.Memory().String()).To(Equal("1Gi"))
+				Expect(pod.Spec.Containers[0].Resources.Limits.Memory().String()).To(Equal("2Gi"))
+			})
+			It("should not add unset resources", func() {
+
+				vm := v1.VirtualMachine{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "testvm",
+						Namespace: "default",
+						UID:       "1234",
+					},
+					Spec: v1.VirtualMachineSpec{
+						Domain: v1.DomainSpec{
+							Resources: v1.ResourceRequirements{
+								Requests: kubev1.ResourceList{
+									kubev1.ResourceCPU:    resource.MustParse("1m"),
+									kubev1.ResourceMemory: resource.MustParse("1Gi"),
+								},
+							},
+						},
+					},
+				}
+
+				pod, err := svc.RenderLaunchManifest(&vm)
+
+				Expect(err).To(BeNil())
+				Expect(pod.Spec.Containers[0].Resources.Requests.Cpu().String()).To(Equal("1m"))
+				Expect(pod.Spec.Containers[0].Resources.Requests.Memory().String()).To(Equal("1Gi"))
+				Expect(pod.Spec.Containers[0].Resources.Limits).To(BeNil())
+			})
+		})
+	})
 
 		Context("with pvc source", func() {
 			It("should add pvc to template", func() {