kubesphere-controls-system下default-http-backend异常告警

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操作系统信息
腾讯云TKE集群 Centos7.6

Kubernetes版本信息
将 kubectl version 命令执行结果贴在下方

Client Version: version.Info{Major:"1", Minor:"18+", GitVersion:"v1.18.4-tke.6", GitCommit:"194201819cf1e5cf45d38f72ce1aac9efca4c7ff", GitTreeState:"clean", BuildDate:"2020-12-25T06:58:56Z", GoVersion:"go1.15.5", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"18+", GitVersion:"v1.18.4-tke.6", GitCommit:"194201819cf1e5cf45d38f72ce1aac9efca4c7ff", GitTreeState:"clean", BuildDate:"2020-12-29T09:13:24Z", GoVersion:"go1.15.6", Compiler:"gc", Platform:"linux/amd64"}

容器运行时
将 docker version / crictl version / nerdctl version 结果贴在下方

Client:
 Version:           18.06.3-ce
 API version:       1.38
 Go version:        go1.10.4
 Git commit:        d7080c1
 Built:             Wed Feb 20 02:24:22 2019
 OS/Arch:           linux/amd64
 Experimental:      false

Server:
 Engine:
  Version:          18.6.3-ce-tke.1
  API version:      1.38 (minimum version 1.12)
  Go version:       go1.10.3
  Git commit:       7f659f6724
  Built:            Thu Aug 20 07:10:40 2020
  OS/Arch:          linux/amd64
  Experimental:     false

KubeSphere版本信息
例如：v2.1.1/v3.0.0。离线安装还是在线安装。在已有K8s上安装还是使用kk安装。

ks版本为从3.0升级到3.1

运行在腾讯云TKE

问题是什么
报错日志是什么，最好有截图。

经常收到下面异常告警

1 alert for  alertname=CPUThrottlingHigh  namespace=kubesphere-controls-system 

Alerts Resolved:
Labels:
- alertname = CPUThrottlingHigh
- cluster = default
- container = default-http-backend
- namespace = kubesphere-controls-system
- pod = default-http-backend-857d7b6856-tc5xh
- prometheus = kubesphere-monitoring-system/k8s
- severity = warning
Annotations:
- message = 26.09% throttling of CPU in namespace kubesphere-controls-system for container default-http-backend in pod default-http-backend-857d7b6856-tc5xh.