// GetContainerInfo returns stats (from Cadvisor) for a container.
func (kl *Kubelet) GetContainerInfo(podFullName string, podUID types.UID, containerName string, req *cadvisorapi.ContainerInfoRequest) (*cadvisorapi.ContainerInfo, error) {
podUID = kl.podManager.TranslatePodUID(podUID)
pods, err := kl.runtimeCache.GetPods()
if err != nil {
return nil, err
}
pod := kubecontainer.Pods(pods).FindPod(podFullName, podUID)
container := pod.FindContainerByName(containerName)
if container == nil {
return nil, kubecontainer.ErrContainerNotFound
}
ci, err := kl.cadvisor.DockerContainer(container.ID.ID, req)
if err != nil {
return nil, err
}
return &ci, nil
}
// relist queries the container runtime for list of pods/containers, compare
// with the internal pods/containers, and generats events accordingly.
func (g *GenericPLEG) relist() {
glog.V(5).Infof("GenericPLEG: Relisting")
if lastRelistTime := g.getRelistTime(); !lastRelistTime.IsZero() {
metrics.PLEGRelistInterval.Observe(metrics.SinceInMicroseconds(lastRelistTime))
}
timestamp := g.clock.Now()
// Update the relist time.
g.updateRelisTime(timestamp)
defer func() {
metrics.PLEGRelistLatency.Observe(metrics.SinceInMicroseconds(timestamp))
}()
// Get all the pods.
podList, err := g.runtime.GetPods(true)
if err != nil {
glog.Errorf("GenericPLEG: Unable to retrieve pods: %v", err)
return
}
pods := kubecontainer.Pods(podList)
g.podRecords.setCurrent(pods)
// Compare the old and the current pods, and generate events.
eventsByPodID := map[types.UID][]*PodLifecycleEvent{}
for pid := range g.podRecords {
oldPod := g.podRecords.getOld(pid)
pod := g.podRecords.getCurrent(pid)
// Get all containers in the old and the new pod.
allContainers := getContainersFromPods(oldPod, pod)
for _, container := range allContainers {
e := computeEvent(oldPod, pod, &container.ID)
updateEvents(eventsByPodID, e)
}
}
var needsReinspection map[types.UID]*kubecontainer.Pod
if g.cacheEnabled() {
needsReinspection = make(map[types.UID]*kubecontainer.Pod)
}
// If there are events associated with a pod, we should update the
// podCache.
for pid, events := range eventsByPodID {
pod := g.podRecords.getCurrent(pid)
if g.cacheEnabled() {
// updateCache() will inspect the pod and update the cache. If an
// error occurs during the inspection, we want PLEG to retry again
// in the next relist. To achieve this, we do not update the
// associated podRecord of the pod, so that the change will be
// detect again in the next relist.
// TODO: If many pods changed during the same relist period,
// inspecting the pod and getting the PodStatus to update the cache
// serially may take a while. We should be aware of this and
// parallelize if needed.
if err := g.updateCache(pod, pid); err != nil {
glog.Errorf("PLEG: Ignoring events for pod %s/%s: %v", pod.Name, pod.Namespace, err)
// make sure we try to reinspect the pod during the next relisting
needsReinspection[pid] = pod
continue
} else if _, found := g.podsToReinspect[pid]; found {
// this pod was in the list to reinspect and we did so because it had events, so remove it
// from the list (we don't want the reinspection code below to inspect it a second time in
// this relist execution)
delete(g.podsToReinspect, pid)
}
}
// Update the internal storage and send out the events.
g.podRecords.update(pid)
for i := range events {
// Filter out events that are not reliable and no other components use yet.
if events[i].Type == ContainerChanged || events[i].Type == ContainerRemoved {
continue
}
g.eventChannel <- events[i]
}
}
if g.cacheEnabled() {
// reinspect any pods that failed inspection during the previous relist
if len(g.podsToReinspect) > 0 {
glog.V(5).Infof("GenericPLEG: Reinspecting pods that previously failed inspection")
for pid, pod := range g.podsToReinspect {
if err := g.updateCache(pod, pid); err != nil {
glog.Errorf("PLEG: pod %s/%s failed reinspection: %v", pod.Name, pod.Namespace, err)
needsReinspection[pid] = pod
}
}
}
// Update the cache timestamp. This needs to happen *after*
// all pods have been properly updated in the cache.
g.cache.UpdateTime(timestamp)
}
// make sure we retain the list of pods that need reinspecting the next time relist is called
g.podsToReinspect = needsReinspection
}