Pod

Autoscaler翻译成中文是POD水平自动伸缩HPA可以基于CPU利用率对replication

controller、deployment和replicaset中的pod数量进行自动扩缩容除了CPU利用率也可以基于其他应程序提供的度量指标custom

metrics进行自动扩缩容。

pod自动缩放不适用于无法缩放的对象比如DaemonSets。

HPA由Kubernetes

API资源和控制器实现。

资源决定了控制器的行为。

控制器会周期性的获取目标资源指标如平均CPU利用率并与目标值相比较后来调整Pod副本数量。

cat

metrics-serverrbac.authorization.k8s.io/aggregate-to-admin:

truerbac.authorization.k8s.io/aggregate-to-edit:

truerbac.authorization.k8s.io/aggregate-to-view:

truename:

system:aggregated-metrics-reader

rules:

metrics-server-auth-readernamespace:

kube-system

extension-apiserver-au***ntication-reader

subjects:

metrics-server:system:auth-delegator

roleRef:apiGroup:

spec:selector:matchLabels:k8s-app:

metrics-serverstrategy:rollingUpdate:maxUnavailable:

0template:metadata:labels:k8s-app:

metrics-serverspec:containers:-

args:-

--kubelet-preferred-address-typesInternalIP,ExternalIP,Hostname-

--kubelet-use-node-status-port-

registry.k8s.io/metrics-server/metrics-server:v0.7.2imagePullPolicy:

IfNotPresentlivenessProbe:failureThreshold:

3httpGet:path:

TCPreadinessProbe:failureThreshold:

3httpGet:path:

200MisecurityContext:allowPrivilegeEscalation:

truerunAsNonRoot:

tmp-dirnodeSelector:kubernetes.io/os:

system-cluster-criticalserviceAccountName:

emptyDir:

metrics.k8s.iogroupPriorityMinimum:

trueservice:name:

metrics-server-587b667b55-tjhfp

1/1

80rootk8s-master:/home/vagrant#

kubectl

spec:scaleTargetRef:apiVersion:

apps/v1kind:

horizontalpodautoscaler.autoscaling/php-apache

Pod

pod/php-apache-67fd659dcb-6z8tz

1/1

pod/php-apache-67fd659dcb-thb68

1/1

horizontalpodautoscaler.autoscaling/php-apache

cpu:

pod/php-apache-67fd659dcb-2hdg5

1/1

pod/php-apache-67fd659dcb-52rcx

1/1

pod/php-apache-67fd659dcb-6z8tz

1/1

pod/php-apache-67fd659dcb-8wc7j

1/1

pod/php-apache-67fd659dcb-8zdf6

1/1

pod/php-apache-67fd659dcb-ckqkm

1/1

pod/php-apache-67fd659dcb-jncsb

1/1

pod/php-apache-67fd659dcb-pb89r

1/1

pod/php-apache-67fd659dcb-t66kv

1/1

pod/php-apache-67fd659dcb-thb68

1/1

horizontalpodautoscaler.autoscaling/php-apache

cpu: