[Kubernetes] Kubernetes Horizontal Pod Autoscaler 테스트
Kubernetes 의 Horizontal Pod Autoscaler(이하 HPA) 를 테스트 해보겠습니다.
부하 테스트 Image 생성
Dockerfile 을 생성합니다.
FROM php:5-apache
ADD index.php /var/www/html/index.php
RUN chmod a+rx index.php
Docker image에 같이 추가 될 index.php 를 생성합니다.
?php
$x = 0.0001;
for ($i = 0; $i <= 1000000; $i++) {
$x += sqrt($x);
}
echo "OK!";
?>
Image 를 Build 합니다.
# docker build -t hpa-example .
Sending build context to Docker daemon 3.072kB
Step 1/3 : FROM php:5-apache
5-apache: Pulling from library/php
5e6ec7f28fb7: Pull complete
cf165947b5b7: Pull complete
7bd37682846d: Pull complete
99daf8e838e1: Pull complete
ae320713efba: Pull complete
ebcb99c48d8c: Pull complete
9867e71b4ab6: Pull complete
936eb418164a: Pull complete
bc298e7adaf7: Pull complete
ccd61b587bcd: Pull complete
b2d4b347f67c: Pull complete
56e9dde34152: Pull complete
9ad99b17eb78: Pull complete
Digest: sha256:0a40fd273961b99d8afe69a61a68c73c04bc0caa9de384d3b2dd9e7986eec86d
Status: Downloaded newer image for php:5-apache
---> 24c791995c1e
Step 2/3 : ADD index.php /var/www/html/index.php
---> bcc3ff35ceb8
Step 3/3 : RUN chmod a+rx index.php
---> Running in d1e173fb27a3
Removing intermediate container d1e173fb27a3
---> f4bb43246866
Successfully built f4bb43246866
Successfully tagged hpa-example:latest
만들어진 이미지를 DockerHub 에 PUSH 합니다.
[root@m01 hpa-example]# docker push han0495/hpa-example
The push refers to repository [docker.io/han0495/hpa-example]
b42dc42a2d18: Pushed
056e15bb815c: Pushed
1aab22401f12: Mounted from library/php
13ab94c9aa15: Mounted from library/php
588ee8a7eeec: Mounted from library/php
bebcda512a6d: Mounted from library/php
5ce59bfe8a3a: Mounted from library/php
d89c229e40ae: Mounted from library/php
9311481e1bdc: Mounted from library/php
4dd88f8a7689: Mounted from library/php
b1841504f6c8: Mounted from library/php
6eb3cfd4ad9e: Mounted from library/php
82bded2c3a7c: Mounted from library/php
b87a266e6a9c: Mounted from library/php
3c816b4ead84: Mounted from library/php
latest: digest: sha256:07c8ebfbe5b8084b878d0ed4ebafe5baad124b0b932e4f56d81480fbf715f03f size: 3449
[root@m01 hpa-example]#
HPA 생성
POD 및 HPA 를 아래와 같이 생성합니다.
[root@m01 hpa-example]# kubectl run php-apache --image=han0495/hpa-example --requests=cpu=200m --expose --port=80
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
service/php-apache created
deployment.apps/php-apache created
[root@m01 hpa-example]# kubectl get po
NAME READY STATUS RESTARTS AGE
php-apache-9bd5c887f-nm4h5 1/1 Running 0 49s
tomcat-f94554bb9-gkhpz 1/1 Running 0 6h28m
web-7d77974d4c-gd76n 1/1 Running 0 7h52m
[root@m01 hpa-example]# curl 10.233.14.29
OK!
[root@m01 hpa-example]# curl 10.233.14.29
OK!
[root@m01 hpa-example]# kubectl autoscale deployment php-apache --cpu-percent=50 --min=1 --max=10
horizontalpodautoscaler.autoscaling/php-apache autoscaled
[root@m01 hpa-example]#
POD 가 생성되고 Build 한 Container Image 가 정상적으로 작동 하는지 확인 하였습니다.
부하 테스트
busybox POD 을 생성하고 HPA 를 생성한 POD 에 부하를 생성합니다.
[root@m01 hpa-example]# kubectl run -i --tty load-generator --image=busybox /bin/sh
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
If you don't see a command prompt, try pressing enter.
/ # while true; do wget -q -O- http://php-apache.default.svc.cluster.local; done
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
OK!
부하가 생성이 되고 일정 시간이 지나면, HPA 에서 리소스 사용량이 증가되고 HPA 는 지정한 MAXPODS 값에 맞게 POD의 수를 증가시킵니다.
Every 2.0s: kubectl get hpa;kubectl get po Tue Apr 9 19:07:57 2019
NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE
php-apache Deployment/php-apache 477%/50% 1 10 4 4m21s
NAME READY STATUS RESTARTS AGE
load-generator-557649ddcd-jq987 1/1 Running 0 4m9s
php-apache-9bd5c887f-8dc4m 0/1 ContainerCreating 0 4s
php-apache-9bd5c887f-bdrlz 1/1 Running 0 20s
php-apache-9bd5c887f-fthkk 0/1 ContainerCreating 0 4s
php-apache-9bd5c887f-g46b8 0/1 ContainerCreating 0 20s
php-apache-9bd5c887f-hq88l 0/1 ContainerCreating 0 4s
php-apache-9bd5c887f-p6lrq 1/1 Running 0 5m11s
php-apache-9bd5c887f-v5bhw 0/1 ContainerCreating 0 4s
php-apache-9bd5c887f-wjlrm 0/1 ContainerCreating 0 20s
부하가 477% 이상 발생되면서 POD 이 자동으로 늘어나는 것을 볼 수 있습니다.
Every 2.0s: kubectl get hpa;kubectl get po Tue Apr 9 19:08:50 2019
NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE
php-apache Deployment/php-apache 189%/50% 1 10 10 5m15s
NAME READY STATUS RESTARTS AGE
load-generator-557649ddcd-jq987 1/1 Running 0 5m2s
php-apache-9bd5c887f-8dc4m 1/1 Running 0 57s
php-apache-9bd5c887f-bdrlz 1/1 Running 0 73s
php-apache-9bd5c887f-crrsq 1/1 Running 0 41s
php-apache-9bd5c887f-fthkk 1/1 Running 0 57s
php-apache-9bd5c887f-g46b8 1/1 Running 0 73s
php-apache-9bd5c887f-hq88l 1/1 Running 0 57s
php-apache-9bd5c887f-p6lrq 1/1 Running 0 6m4s
php-apache-9bd5c887f-v5bhw 1/1 Running 0 57s
php-apache-9bd5c887f-vs6sl 1/1 Running 0 42s
php-apache-9bd5c887f-wjlrm 1/1 Running 0
HPA 가 POD 을 MAXPODS 수까지 생성하였습니다.
Every 2.0s: kubectl get hpa;kubectl get po Tue Apr 9 19:14:41 2019
NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE
php-apache Deployment/php-apache 0%/50% 1 10 10 11m
NAME READY STATUS RESTARTS AGE
load-generator-557649ddcd-jq987 1/1 Running 0 10m
php-apache-9bd5c887f-bdrlz 0/1 Terminating 0 7m4s
php-apache-9bd5c887f-fthkk 0/1 Terminating 0 6m48s
php-apache-9bd5c887f-g46b8 0/1 Terminating 0 7m4s
php-apache-9bd5c887f-hq88l 0/1 Terminating 0 6m48s
php-apache-9bd5c887f-p6lrq 1/1 Running 0 11m
php-apache-9bd5c887f-vs6sl 0/1 Terminating 0 6m33s
부하가 중지되면 HPA는 다시 POD의 수를 줄입니다.