HPA在使用AverageValue而不是Utilization时不缩放pod

Question

我正在阅读kubernetes文档中的HPA演练。当使用平均值而不是利用率时，我无法让HPA扩展部署。

我使用的是1.25 minikube集群，并且已经部署了度量服务器并打了补丁。

kubectl patch deployment metrics-server -n kube-system --type 'json' -p '[{"op": "add", "path": "/spec/template/spec/containers/0/args/-", "value": "--kubelet-insecure-tls"}]'

我能够成功执行Kubectl top pods/nodes命令成功，这对我来说意味着度量服务器工作正常。

Gauravs-MBP:K8s alieninvader$ kubectl top pods
NAME                          CPU(cores)   MEMORY(bytes)   
load-generator                6m           0Mi             
php-apache-5b56f9df94-r74qk   501m         11Mi            
Gauravs-MBP:K8s alieninvader$ kubectl top nodes
NAME       CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%   
minikube   719m         11%    834Mi           10%       

当我使用Utilization而不是AverageValue时，HPA能够扩展部署。我使用了相同的php-apache部署，并使用它作为我的清单来创建HPA。

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
name: php-apache
namespace: default
spec:
maxReplicas: 10
metrics:
- resource:
name: cpu
target:
averageValue: 50
type: AverageValue
type: Resource
minReplicas: 1
scaleTargetRef:
apiVersion: apps/v1
kind: Deployment
name: php-apache

当我查看HPA的事件时，我看到HPA仍然将其计算为在推荐范围内。

kubectl describe hpa php-apache
Warning: autoscaling/v2beta2 HorizontalPodAutoscaler is deprecated in v1.23+, unavailable in v1.26+; use autoscaling/v2 HorizontalPodAutoscaler
Name:                    php-apache
Namespace:               default
Labels:                  <none>
Annotations:             <none>
CreationTimestamp:       Tue, 20 Dec 2022 13:43:19 -0500
Reference:               Deployment/php-apache
Metrics:                 ( current / target )
resource cpu on pods:  501m / 50
Min replicas:            1
Max replicas:            10
Deployment pods:         1 current / 1 desired
Conditions:
Type            Status  Reason              Message
----            ------  ------              -------
AbleToScale     True    ReadyForNewScale    recommended size matches current size
ScalingActive   True    ValidMetricFound    the HPA was able to successfully calculate a replica count from cpu resource
ScalingLimited  False   DesiredWithinRange  the desired count is within the acceptable range
Events:           <none>

Gauravs-MBP:K8s alieninvader$ kubectl get hpa -w
NAME         REFERENCE               TARGETS   MINPODS   MAXPODS   REPLICAS   AGE
php-apache   Deployment/php-apache   1m/50     1         10        1          37s
php-apache   Deployment/php-apache   189m/50   1         10        1          45s
php-apache   Deployment/php-apache   501m/50   1         10        1          60s
php-apache   Deployment/php-apache   502m/50   1         10        1          90s
php-apache   Deployment/php-apache   500m/50   1         10        1          105s
php-apache   Deployment/php-apache   501m/50   1         10        1          2m
php-apache   Deployment/php-apache   500m/50   1         10        1          2m15s
php-apache   Deployment/php-apache   501m/50   1         10        1          2m30s
php-apache   Deployment/php-apache   499m/50   1         10        1          2m45s
php-apache   Deployment/php-apache   502m/50   1         10        1          3m
php-apache   Deployment/php-apache   501m/50   1         10        1          3m15s
php-apache   Deployment/php-apache   500m/50   1         10        1          3m30s
php-apache   Deployment/php-apache   501m/50   1         10        1          3m45s
php-apache   Deployment/php-apache   500m/50   1         10        1          4m
php-apache   Deployment/php-apache   502m/50   1         10        1          4m15s
php-apache   Deployment/php-apache   500m/50   1         10        1          4m30s
php-apache   Deployment/php-apache   501m/50   1         10        1          4m45s
php-apache   Deployment/php-apache   500m/50   1         10        1          5m
php-apache   Deployment/php-apache   501m/50   1         10        1          5m15s
php-apache   Deployment/php-apache   500m/50   1         10        1          5m30s
php-apache   Deployment/php-apache   501m/50   1         10        1          5m45s
php-apache   Deployment/php-apache   500m/50   1         10        1          6m15s
php-apache   Deployment/php-apache   502m/50   1         10        1          6m30s
php-apache   Deployment/php-apache   500m/50   1         10        1          6m45s

那么，为什么当使用AverageValue时，HPA认为这是在范围内，而kubectl中显示的CPU百分比显然要高得多。我错过了什么?

Answer 1

与averageUtilization相反，averageValue应该是一个文字值，而不是百分比(参见MetricTarget)。在您的设置中，它被设置为50核，这显然比pod上的负载高得多。你是说500米吗?