当前位置：网站首页>Kubernetes ---- pod configuration resource quota

Kubernetes ---- pod configuration resource quota

2022-07-26 14:32:00 【51CTO】

One 、Pod Resource quotas

1.1 Introduction to resource quota configuration

The program in the container needs to run , It must take up some resources , such as CPU Memory and so on. , If you don't limit the resources of a container , Then it may eat a lot of resources , Cause the gas container to fail to operate , In this case ,kubernetes Provides access to memory and CPU A mechanism for allocating resources , This mechanism is mainly through resources Option class implementation , It has two sub options

limits： Used to limit the maximum resources used by the runtime container , When the container takes up more than limits Will be terminated , And restart
requests： Used to set the minimum resource required by the container , If environmental resources are not enough , The container cannot start

1.2 Resource quota configuration

as follows , edit pod_base.yaml file , Yes nginx The container sets the upper and lower resource limits

       
       apiVersion
       
       : v1
       
       kind
       
       : Namespace
       
       metadata
       
       :
       
        name
       
       : dev
       
       ---
       
       apiVersion
       
       : v1
       
       kind
       
       : Pod
       
       metadata
       
       :
       
        name
       
       : pod-resources
       
        namespace
       
       : dev
       
        labels
       
       :
       
        user
       
       : redrose2100
       
       spec
       
       :
       
        containers
       
       :
       
        - 
       
       name
       
       : nginx
       
        image
       
       : nginx
       
       :
       
       1.17.1
       
        resources
       
       :
       
        requests
       
       :
       
        cpu
       
       : 
       
       "1"
       
        memory
       
       : 
       
       "100M"
       
        limits
       
       :
       
        cpu
       
       : 
       
       "2"
       
        memory
       
       : 
       
       "512M"
      
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.

Use the following command to create pod

       
       [[email protected] pod]
       
       # kubectl apply -f pod_resources.yaml
       
namespace/dev created
       
pod/pod-resources created
       
[[email protected] pod]
       
       #
      
1.
2.
3.
4.

Use the following command to query pod, Find the quota configuration at this time , The environment meets the requirements ,pod It starts normally

       
       [[email protected] pod]
       
       # kubectl get pod -n dev
       
NAME            READY   STATUS    RESTARTS   AGE
       
pod-resources   
       
       1/1     Running   
       
       0          7s
       
[[email protected] pod]
       
       #
      
1.
2.
3.
4.

Use the following command to delete the resource

       
       [[email protected] pod]
       
       # kubectl delete -f pod_resources.yaml
       
namespace 
       
       "dev" deleted
       
pod 
       
       "pod-resources" deleted
       
[[email protected] pod]
       
       #
      
1.
2.
3.
4.

1.3 Quota over allocation test

You can do an experiment here , take cpu Modify the lower limit to 10, The upper limit is changed to 20, Then try again , Because the core count of the virtual machine here is 4, Modify the lower limit to 10 The latter is obviously unable to meet the requirements

       
       apiVersion
       
       : v1
       
       kind
       
       : Namespace
       
       metadata
       
       :
       
        name
       
       : dev
       
       ---
       
       apiVersion
       
       : v1
       
       kind
       
       : Pod
       
       metadata
       
       :
       
        name
       
       : pod-resources
       
        namespace
       
       : dev
       
        labels
       
       :
       
        user
       
       : redrose2100
       
       spec
       
       :
       
        containers
       
       :
       
        - 
       
       name
       
       : nginx
       
        image
       
       : nginx
       
       :
       
       1.17.1
       
        resources
       
       :
       
        requests
       
       :
       
        cpu
       
       : 
       
       "10"
       
        memory
       
       : 
       
       "100M"
       
        limits
       
       :
       
        cpu
       
       : 
       
       "20"
       
        memory
       
       : 
       
       "512M"
      
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.

Then create it using the following command ：

       
       [[email protected] pod]
       
       # kubectl apply -f pod_resources.yaml
       
namespace/dev created
       
pod/pod-resources created
       
[[email protected] pod]
       
       #
      
1.
2.
3.
4.

After re creation, you can see the prompt here through the following command cpu It's not enough

       
       [[email protected] pod]
       
       # kubectl get pod -n dev
       
NAME            READY   STATUS    RESTARTS   AGE
       
pod-resources   
       
       0/1     Pending   
       
       0          17m
       
[[email protected] pod]
       
       # kubectl describe pod pod-resources -n dev
       
Name:         pod-resources
       
Namespace:    dev
       
Priority:     
       
       0
       
Node:         <none>
       
Labels:       
       
       user
       
       =redrose2100
       
Annotations:  <none>
       
Status:       Pending
       
IP:
       
IPs:          <none>
       
Containers:
       
  nginx:
       
    Image:      nginx:1.17.1
       
    Port:       <none>
       
    Host Port:  <none>
       
    Limits:
       
      cpu:     
       
       20
       
      memory:  512M
       
    Requests:
       
      cpu:        
       
       10
       
      memory:     100M
       
    Environment:  <none>
       
    Mounts:
       
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-8kvvb (ro)
       
Conditions:
       
  Type           Status
       
  PodScheduled   False
       
Volumes:
       
  kube-api-access-8kvvb:
       
    Type:                    Projected (a volume that contains injected data from multiple sources)
       
    TokenExpirationSeconds:  
       
       3607
       
    ConfigMapName:           kube-root-ca.crt
       
    ConfigMapOptional:       <nil>
       
    DownwardAPI:             
       
       true
       
QoS Class:                   Burstable
       
Node-Selectors:              <none>
       
Tolerations:                 
       
       node.kubernetes.io/not-ready:NoExecute 
       
       op
       
       =Exists 
       
       for 300s
       
       node.kubernetes.io/unreachable:NoExecute 
       
       op
       
       =Exists 
       
       for 300s
       
Events:
       
  Type     Reason            Age                 From               Message
       
       --
       
       --     
       
       --
       
       --
       
       --            
       
       --
       
       --                
       
       --
       
       --               
       
       --
       
       --
       
       --
       
       -
       
  Warning  FailedScheduling  38s (x19 over 18m)  default-scheduler  
       
       0/3 nodes are available: 
       
       1 
       
       node(s) had taint {node-role.kubernetes.io/master: }, that the pod didn
       
       't tolerate, 2 Insufficient cpu.
       
       [[email protected] pod]#
      
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.

Use the following command to delete the resource

       
       [[email protected] pod]
       
       # kubectl delete -f pod_resources.yaml
       
namespace 
       
       "dev" deleted
       
pod 
       
       "pod-resources" deleted
       
[[email protected] pod]
       
       #
      
1.
2.
3.
4.