Documentation
¶
Overview ¶
package qos contains helper functions for quality of service. For each resource (memory, CPU) Kubelet supports three classes of containers. Memory guaranteed containers will receive the highest priority and will get all the resources they need. Burstable containers will be guaranteed their request and can “burst” and use more resources when available. Best-Effort containers, which don’t specify a request, can use resources only if not being used by other pods.
Index ¶
Constants ¶
const (
// PodInfraOOMAdj is very docker specific. For arbitrary runtime, it may not make
// sense to set sandbox level oom score, e.g. a sandbox could only be a namespace
// without a process.
// TODO: Handle infra container oom score adj in a runtime agnostic way.
// TODO: Should handle critical pod oom score adj with a proper preemption priority.
// This is the workaround for https://github.com/kubernetes/kubernetes/issues/38322.
PodInfraOOMAdj int = -998
CriticalPodOOMAdj int = -998
KubeletOOMScoreAdj int = -999
DockerOOMScoreAdj int = -999
KubeProxyOOMScoreAdj int = -999
)
Variables ¶
This section is empty.
Functions ¶
func GetContainerOOMScoreAdjust ¶ added in v1.2.0
func GetContainerOOMScoreAdjust(pod *api.Pod, container *api.Container, memoryCapacity int64) int
GetContainerOOMAdjust returns the amount by which the OOM score of all processes in the container should be adjusted. The OOM score of a process is the percentage of memory it consumes multiplied by 10 (barring exceptional cases) + a configurable quantity which is between -1000 and 1000. Containers with higher OOM scores are killed if the system runs out of memory. See https://lwn.net/Articles/391222/ for more information.
Types ¶
type QOSClass ¶ added in v1.4.0
type QOSClass string
QOSClass defines the supported qos classes of Pods/Containers.
const (
// Guaranteed is the Guaranteed qos class.
Guaranteed QOSClass = "Guaranteed"
// Burstable is the Burstable qos class.
Burstable QOSClass = "Burstable"
// BestEffort is the BestEffort qos class.
BestEffort QOSClass = "BestEffort"
)
func GetPodQOS ¶ added in v1.4.0
func GetPodQOS(pod *api.Pod) QOSClass
GetPodQOS returns the QoS class of a pod. A pod is besteffort if none of its containers have specified any requests or limits. A pod is guaranteed only when requests and limits are specified for all the containers and they are equal. A pod is burstable if limits and requests do not match across all containers.
Source Files