Scaling a Workload

This section describes two workload scaling methods: auto scaling and manual scaling.

• Auto scaling: Supports metric-based, scheduled, and periodic policies. When the configuration is complete, pods can be automatically added or deleted based on resource changes or a specified schedule.
• Manual scaling: Increases or decreases the number of pods immediately after the configuration is complete.

If a pod mounted with an EVS volume is deleted, the EVS disk will not be deleted. If a new pod with the same name is created, the new pod cannot be mounted to any EVS volume.

Auto Scaling

Currently, auto scaling is supported only for Deployments.

An appropriate auto scaling policy eliminates the need to manually adjust resources in response to service changes and traffic peaks, thus helping you reduce the workforce and resources required. CCI supports the following types of auto scaling policies:

Metric-based: Scales the workload based on CPU/memory usage. You can specify a CPU/memory usage threshold. If the usage is higher or lower than the threshold, instances can be automatically added or deleted.

Scheduled: Scales the workload at a specified time. A scheduled scaling policy is ideal for scenarios such as flash sales and anniversary promotions.

Periodic: Scales the workload on a daily, weekly, or monthly basis. A periodic scaling policy is ideal for applications that have periodic traffic changes.

• Configure a metric-based auto scaling policy.
  1. Log in to the CCI console. In the navigation pane on the left, choose Workloads > Deployments. On the page displayed, click the target Deployment.
  2. In the Scaling area of the Deployment details page, click Auto Scaling and then click Add Scaling Policy.
     Figure 1 Adding a metric-based auto scaling policy
     

     Table 1 Parameters of a metric-based auto scaling policy

     Parameter	Description
     Policy Name	Enter a name for the policy.
     Policy Type	Select Metric-based policy.
     Trigger Condition	Select CPU usage or Memory usage. If you set the trigger condition to average memory usage > 70%, the scaling policy will be triggered when the average memory usage exceeds 70%.
     Duration	Statistical period. Select a value from the drop-down list. If you set this parameter to 60, metric statistics will be collected every 60 seconds.
     Consecutive Times	If you set this parameter to 3, the configured action will be triggered when the threshold is reached for 3 consecutive statistical periods.
     Policy Action	Specify the action to be executed when the policy is triggered. You can specify an action to add or reduce the number of instances.

  3. Click OK.
     The policy is added to the policy list, and its status is Enabled.

     Figure 2 Policy enabled
     

     When the trigger condition is met, the auto scaling policy will be executed.

• Configure a scheduled auto scaling policy.
  1. In the Scaling area, click Auto Scaling and then click Add Scaling Policy.
     Figure 3 Adding a scheduled auto scaling policy
     

     Table 2 Parameters of a scheduled auto scaling policy

     Parameter	Description
     Policy Name	Enter a name for the policy.
     Policy Type	Select Scheduled Policy.
     Triggered	Specify the time when you want the policy to be triggered.
     Policy Action	Specify the action to be executed when the policy is triggered. You can specify an action to add or reduce the number of instances.

  2. Click OK.

     The policy is added to the policy list, and its status is Enabled.

• Configure a periodic auto scaling policy.
  1. In the Scaling area, click Auto Scaling and then click Add Scaling Policy.
     Figure 4 Adding a periodic auto scaling policy
     

     Table 3 Parameters of a periodic auto scaling policy

     Parameter	Description
     Policy Name	Enter a name for the policy.
     Policy Type	Select Periodic Policy.
     Select Time	Select the time range, frequency, and time when you want the policy to be triggered.
     Policy Action	Specify the action to be executed when the policy is triggered.

  2. Click OK.

     The policy is added to the policy list, and its status is Enabled.