InPlace Pod Vertical Scaling feature - review fixes, initial e2e tests

1. Add framework code for e2e testing, and example e2e tests.
2. Do container resource update based on difference between requests as well as limits.
KEP: /enhancements/keps/sig-node/20181106-in-place-update-of-pod-resources.md

pkg/kubelet/cm/cgroup_manager_linux.go

@@ -22,6 +22,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"sync"
 	"time"

pkg/kubelet/cm/helpers_unsupported.go

@@ -29,6 +29,7 @@ const (
 	MilliCPUToCPU = 0
 
 	MinQuotaPeriod = 0
+	QuotaPeriod    = 0
 )
 
 // MilliCPUToQuota converts milliCPU and period to CFS quota values.

pkg/kubelet/kuberuntime/kuberuntime_manager.go

@@ -633,12 +633,16 @@ func (m *kubeGenericRuntimeManager) computePodActions(pod *v1.Pod, podStatus *ku
 				if container.Resources.Limits == nil || len(pod.Status.ContainerStatuses) == 0 {
 					continue
 				}
+				// Determine if the *running* container needs resource update by comparing Spec.Resources (desired)
+				// with Status.Resources (last known actual). This check is done when kubelet has accepted the
+				// resize a.k.a Resources.Requests == ResourcesAllocated.
+				// Skip if runtime container ID does not match pod.Status containerID as container may be restarting
 				apiContainerStatus, exists := podutil.GetContainerStatus(pod.Status.ContainerStatuses, container.Name)
 				if !exists || apiContainerStatus.State.Running == nil ||
 					containerStatus.State != kubecontainer.ContainerStateRunning ||
 					containerStatus.ID.String() != apiContainerStatus.ContainerID ||
 					len(diff.ObjectDiff(container.Resources.Requests, container.ResourcesAllocated)) != 0 ||
-					len(diff.ObjectDiff(apiContainerStatus.Resources.Limits, container.Resources.Limits)) == 0 {
+					len(diff.ObjectDiff(apiContainerStatus.Resources, container.Resources)) == 0 {
 					continue
 				}
 				resizePolicy := make(map[v1.ResourceName]v1.ContainerResizePolicy)

test/e2e/common/BUILD

@@ -25,6 +25,7 @@ go_library(
         "lifecycle_hook.go",
         "networking.go",
         "node_lease.go",
+        "pod_resize.go",
         "pods.go",
         "podtemplates.go",
         "privileged.go",
@@ -46,6 +47,7 @@ go_library(
         "//pkg/api/v1/pod:go_default_library",
         "//pkg/client/conditions:go_default_library",
         "//pkg/kubelet:go_default_library",
+        "//pkg/kubelet/cm:go_default_library",
         "//pkg/kubelet/events:go_default_library",
         "//pkg/kubelet/images:go_default_library",
         "//pkg/kubelet/runtimeclass/testing:go_default_library",
@@ -67,10 +69,12 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/uuid:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/watch:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
         "//staging/src/k8s.io/client-go/dynamic:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
         "//staging/src/k8s.io/client-go/tools/cache:go_default_library",
         "//staging/src/k8s.io/client-go/tools/watch:go_default_library",
+        "//staging/src/k8s.io/component-base/featuregate:go_default_library",
         "//test/e2e/framework:go_default_library",
         "//test/e2e/framework/events:go_default_library",
         "//test/e2e/framework/network:go_default_library",