Container Service for Kubernetes:Resource profiling

Limits

Use resource profiling in the ACK console

Step 1: Install the resource profiling component

1. Log on to the ACK console. In the left-side navigation pane, click Clusters.

2. On the Clusters page, click the name of the cluster that you want to manage and choose Cost Suite > Cost Optimization in the left-side navigation pane.

3. On the Cost Optimization page, click the Resource Profiling tab, and follow the instructions in the Resource Profiling section to enable this feature.

   • Follow the instructions on the page to install or update the ack-koordinator component. If this is the first time you use resource profiling, you need to install the ack-koordinator component.

     Note

     If an ack-koordinator version earlier than 0.7.0 is used, you need to perform a migration and update. For more information, see Migrate ack-koordinator from the Marketplace page to the Add-ons page.

   • If this is the first time you use resource profiling, after the component is installed or updated, we recommend that you select Default Settings to enable resource profiling for all workloads. You can click Profiling Configuration to modify the applicable scope of resource profiling later.

4. Click Enable Resource Profiling to go to the Resource Profiling tab.

Step 2: Manage resource profiling policies

1. Log on to the ACK console. In the left-side navigation pane, click Clusters.

2. On the Clusters page, click the name of the cluster that you want to manage and choose Cost Suite > Cost Optimization in the left-side navigation pane.

3. On the Cost Optimization page, click the Resource Profiling tab, and then click Profiling Configuration.

   You can choose Global Configuration or Custom Configuration. The default settings that you selected when you install the resource profiling component belong to the global configuration. You can choose Global Configuration, modify the settings, and then click OK to apply the modifications.

   Global configuration mode (recommended)

   In global configuration mode, resource profiling is enabled for workloads other than those in the arms-prom and kube-system namespaces by default.

   Parameter	Description	Valid value
   Excluded Namespace	The namespaces for which you want to disable resource profiling. In most cases, resource profiling is disabled for the namespaces of system components. After you modify the global configuration, resource profiling is enabled only for workloads of the specified types that do not belong to the excluded namespaces.	You can specify one or more existing namespaces in the cluster. By default, the kube-system and arms-prom namespaces are specified.
   Workload Type	The types of workloads for which resource profiling is enabled. After you modify the global configuration, resource profiling is enabled only for workloads of the specified types that do not belong to the excluded namespaces.	The following Kubernetes workloads are supported: Deployment, StatefulSet, and DaemonSet. You can select one or more workload types.
   CPU Redundancy Rate/Memory Redundancy Rate	The redundancy rate that is specified in the resource profiling policy. For more information, see the following section.	The redundancy rate must be 0 or a positive value. The system also provides three commonly used redundancy rates: 70%, 50%, and 30%.

   Custom configuration mode

   In custom configuration mode, resource profiling is enabled only for partial workloads. If your cluster is large (with more than 1,000 nodes) or you want to enable resource profiling for partial workloads, choose the custom configuration mode.

   Parameter	Description	Valid value
   Namespace	The namespaces for which you want to enable resource profiling. After you modify the custom configuration, resource profiling is enabled for workloads of the specified types that belong to the selected namespaces.	You can select one or more existing namespaces in the cluster.
   Workload Type	The workload types for which you want to enable resource profiling. After you modify the custom configuration, resource profiling is enabled for workloads of the specified types that belong to the selected namespaces.	The following Kubernetes workloads are supported: Deployment, StatefulSet, and DaemonSet. You can select one or more workload types.
   CPU Redundancy Rate/Memory Redundancy Rate	The redundancy rate that is specified in the resource profiling policy. For more information, see the following section.	The redundancy rate must be 0 or a positive value. The system also provides three commonly used redundancy rates: 70%, 50%, and 30%.

   Resource redundancy: When an administrator assesses the workloads of an application, such as the QPS of the application, the administrator usually assumes that the workloads will not occupy 100% physical resources. This is because even technologies such as hyper-threading have limits on physical resources and the application also needs to reserve resources to handle traffic spikes during peak hours. If the difference between the suggested resource request and the original resource request exceeds the specified redundancy rate, the system suggests that you decrease the resource request. For more information about the resource profiling algorithm, see the Overview of application profiles section.

Step 3: View resource profiles

After you configure the resource profiling policy, you can view the resource profiles of the workloads on the Resource Profiling page.

To ensure the accuracy of resource profiles, if this is the first time you use resource profiling, you need to wait at least 24 hours for the system to collect data.

This page displays the aggregated resource profile data and the resource profile of each workload.

Step 4: View the details of a resource profile

Step 5: Modify resource configurations

Use resource profiling with the CLI

Step 1: Enable resource profiling

1. Use the following YAML template to create a file named recommendation-profile.yaml and enable resource profiling for your workloads.

   You can use the RecommendationProfile CRD to generate resource profiles for your workloads and obtain resource configuration suggestions. You can specify the namespaces and workload types to which a RecommendationProfile CRD is applied.

   apiVersion: autoscaling.alibabacloud.com/v1alpha1
   kind: RecommendationProfile
   metadata:
     # The name of the RecommendationProfile CRD. If you want to create a non-namespaced RecommendationProfile CRD, do not specify a namespace. 
     name: profile-demo
   spec:
     # The workload types for which you want to enable resource profiling. 
     controllerKind:
     - Deployment
     # The namespaces for which you want to enable resource profiling. 
     enabledNamespaces:
     - default

   The following table describes the parameters in the YAML template.

   Parameter	Type	Description
   metadata.name	String	The name of the resource object. If you want to create a non-namespaced RecommendationProfile CRD, do not specify a namespace.
   spec.controllerKind	String	The workload types for which you want to enable resource profiling. Valid values: Deployment, StatefulSet, and DaemonSet.
   spec.enabledNamespaces	String	The namespaces for which you want to enable resource profiling.

2. Run the following command to enable resource profiling for the application that you created:

   kubectl apply -f recommender-profile.yaml

3. Create a file named cpu-load-gen.yaml and copy the following content to the file:

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: cpu-load-gen
     labels:
       app: cpu-load-gen
   spec:
     replicas: 2
     selector:
       matchLabels:
         app: cpu-load-gen-selector
     template:
       metadata:
         labels:
           app: cpu-load-gen-selector
       spec:
         containers:
         - name: cpu-load-gen
           image: registry.cn-zhangjiakou.aliyuncs.com/acs/slo-test-cpu-load-gen:v0.1
           command: ["cpu_load_gen.sh"]
           imagePullPolicy: Always
           resources:
             requests:
               cpu: 8 # Request eight CPU cores for the application. 
               memory: "1Gi"
             limits:
               cpu: 12
               memory: "2Gi"

4. Run the following command to apply cpu-load-gen.yaml and deploy the cpu-load-gen application:

   kubectl apply -f cpu-load-gen.yaml

5. Run the following command to obtain resource configuration suggestions for the application that you created:

   kubectl get recommendations -l \
     "alpha.alibabacloud.com/recommendation-workload-apiVersion=apps-v1, \
     alpha.alibabacloud.com/recommendation-workload-kind=Deployment, \
     alpha.alibabacloud.com/recommendation-workload-name=cpu-load-gen" -o yaml

   Note

   To generate accurate resource configuration suggestions, we recommend that you wait at least one day after you enable resource profiling for the system to collect data.

   After you enable resource profiling for your workloads, ack-slo-manager provides resource configuration suggestions for your workloads. The suggestions are stored in the Recommendation CRD. The following code block shows a resource profile named cpu-load-gen.yaml.

   apiVersion: autoscaling.alibabacloud.com/v1alpha1
   kind: Recommendation
   metadata:
     labels:
       alpha.alibabacloud.com/recommendation-workload-apiVersion: app-v1
       alpha.alibabacloud.com/recommendation-workload-kind: Deployment
       alpha.alibabacloud.com/recommendation-workload-name: cpu-load-gen
     name: f20ac0b3-dc7f-4f47-b3d9-bd91f906****
     namespace: recommender-demo
   spec:
     workloadRef:
       apiVersion: apps/v1
       kind: Deployment
       name: cpu-load-gen
   status:
     recommendResources:
       containerRecommendations:
       - containerName: cpu-load-gen
         target:
           cpu: 4742m
           memory: 262144k
         originalTarget: #The intermediate result generated by the resource profiling algorithm. We recommend that you do not use the intermediate result. 
          # ...

   To facilitate data retrieval, the Recommendation CRD is generated in the same namespace as the workload. In addition, the Recommendation CRD saves the API version, type, and name of the workload in the labels described in the following table.

   Label key	Description	Example
   alpha.alibabacloud.com/recommendation-workload-apiVersion	The API version of the workload. The value of the label conforms to the Kubernetes specifications. Forward slashes (/) are replaced by hyphens (-).	app-v1 (Original form: app/v1)
   alpha.alibabacloud.com/recommendation-workload-kind	The type of the workload, for example, Deployment or StatefulSet.	Deployment
   alpha.alibabacloud.com/recommendation-workload-name	The name of the workload. The value of the label conforms to the Kubernetes specifications and cannot exceed 63 characters in length.	cpu-load-gen

   The resource profiling result of each container is saved in status.recommendResources.containerRecommendations. The following table describes the parameters.

   Parameter	Description	Format	Example
   containerName	The name of the container.	string	cpu-load-gen
   target	The resource profiling result, including the suggested CPU request and memory request.	map[ResourceName]resource.Quantity	cpu: 4742mmemory: 262144k
   originalTarget	The intermediate result generated by the resource profiling algorithm. We recommend that you do not use the intermediate result. If you have any requirements, submit a ticket.	-	-

   Note

   The suggested minimum CPU resources are 0.025 CPU cores. The suggested minimum memory resources are 250 MB.

   Compare the resource configurations requested by the cpu-load-gen.yaml application and the suggested resource configurations in this step. The requested CPU resources are greater than the suggested CPU resources. You can reduce the CPU request of the application to save resources.

   Resource	Requested amount	Suggested amount
   CPU	8 CPU cores	4.742 CPU cores

Step 2. (Optional): Verify the profiling results in Managed Service for Prometheus

FAQ

How does the resource profiling algorithm work?

What types of applications is suitable for resource profiling?

Resource profiling is suitable for online applications.

In most cases, the resource configurations suggested by the resource profiling feature can meet the resource requirements of your applications. Offline applications use batch processing and require high throughput. Offline applications allow resource contention so as to improve resource utilization. If you enable resource profiling for offline applications, resource waste may occur. In most cases, key system components are deployed in active/standby mode and have multiple replicas. In most cases, the resources that are allocated to standby replicas are idle. As a result, the results generated by the resource profiling algorithm are not accurate. In the preceding cases, we recommend that you do not use the resource configurations suggested by resource profiling. ACK will provide updates on how to specify resource configurations based on the suggestions provided by resource profiling in these cases.

Can I directly use the resource configurations suggested by resource profiling when I specify the resource request and resource limit of a container?

Resource profiling generates resource configuration suggestions based on the current resource demand of an application. Administrators need to take business characteristics into consideration and modify the suggested values accordingly. For example, you may need to reserve resources to handle traffic spikes or reserve resources for zone-disaster recovery. You may also need to increase the suggested values to ensure that resource-thirsty applications can run stably when the loads of the host are high.

How do I view resource profiles if I use a self-managed Prometheus monitoring system?

You can configure Grafana dashboards to view resource profiles. For more information, see Step 2. (Optional): Verify the profiling results in Managed Service for Prometheus.

How do I delete resource profiles and resource profiling policies?

Resource profiles are stored in the Recommendation CRD. Resource profiling policies are stored in the RecommendationProfile CRD. You can run the following command to delete all resource profiles and resource profiling policies:

# Delete all resource profiles. 
kubectl delete recommendation -A --all

# Delete all resource profiling policies. 
kubectl delete recommendationprofile -A --all