Tair (Redis® OSS-Compatible):Enable bandwidth auto scaling

Prerequisites

The instance is a Redis Community Edition or Tair (Enterprise Edition) memory-optimized or persistent memory-optimized instance.

Function overview

Because different instance types have different bandwidth limits, if traffic exceeds the bandwidth limit, blocking may occur, which affects service performance. You can enable the bandwidth auto scaling feature to avoid such situations. Compared with changing the instance type, adjusting bandwidth helps you quickly increase bandwidth, reduce overall costs, and avoid connection interruptions, allowing for immediate use.

Feature limitations

• After the bandwidth of an instance is automatically increased, the system waits for at least 1 hour before it can automatically decrease the bandwidth. Additionally, there is a 1-minute cooling period between two automatic bandwidth increase operations.

• The bandwidth of an instance can be increased by up to six times the default bandwidth of the instance type, with a maximum increment of 192 MB/s.

  Note

  For example:

  • The default bandwidth of a 2 GB standard Tair memory-optimized instance is 96 MB/s. The maximum bandwidth of this instance can be 96 MB/s + 192 MB/s = 288 MB/s.

  • The default bandwidth of a 256 MB standard Redis Community Edition instance is 10 MB/s. The maximum additional bandwidth for this instance type is 60 MB/s. Therefore, the maximum bandwidth of the instance is 10 MB/s + 60 MB/s = 70 MB/s.

  If you need a higher bandwidth, you can upgrade the instance type or architecture (for example, from standard architecture to cluster architecture) to obtain higher bandwidth performance. For more information, see Instance types.

• We recommend that you do not manually adjust the instance bandwidth and enable bandwidth auto scaling for the instance at the same time.

  If you use both features at the same time: When the manually set bandwidth reaches the upper limit, automatic bandwidth increase is no longer triggered. As traffic decreases, automatic bandwidth decrease reduces the manually set bandwidth to the default bandwidth of the instance type.

  Note

  For example:

  • If the default bandwidth of an instance is 10 MB/s and you manually set it to 70 MB/s, when the increase threshold is reached, the bandwidth is not automatically increased because it exceeds the 6× scaling limit.

  • If you manually set the bandwidth of an instance of the same type to 40 MB/s, when the increase threshold is reached, the bandwidth can be automatically increased to a maximum of 70 MB/s. When the decrease threshold is reached, the bandwidth is decreased until it reaches the default bandwidth of 10 MB/s.

• If an instance has unexpired bandwidth plans, you cannot enable bandwidth auto scaling for the instance. You must first unsubscribe from the bandwidth plans of the instance. For more information, see Unsubscription management.

• If you perform one of the following operations, bandwidth auto scaling is disabled for your instance. You must re-enable this feature for the instance based on your needs:

  Operation	Exception
  Major version upgrade	None
  Change the configurations of an instance	If the instance uses the standard architecture, the bandwidth settings remain valid after you change the specifications of the instance.
  Change the zone of an instance	If the instance uses the standard architecture, the bandwidth settings remain valid after you migrate the instance across zones.

Procedure

1. Log on to the console and go to the Instances page. In the top navigation bar, select the region in which the instance that you want to manage resides. Then, find the instance and click the instance ID.

2. In the Configuration Information section, click Modify next to Maximum Bandwidth.

   Note

   The first time you log on to the DAS console, follow the instructions to grant permissions to your account.

3. Turn on the switch to enable Auto Bandwidth Scaling.

4. In the DAS console dialog box that appears, configure the bandwidth auto scaling policy and event subscription settings.

   1. Configure the bandwidth auto scaling policy.

      Category	Parameter	Description
      Auto Bandwidth Increase	Auto Bandwidth Increase	Select the check box to enable the feature.
      	Average Bandwidth Usage Not Less Than	The increase threshold. Select the average bandwidth usage threshold that triggers automatic bandwidth increase. Unit: %. Valid values: 50% to 95%. Note The system uses the larger value between the inbound traffic and outbound traffic average usage as the Average Bandwidth Usage. The bandwidth of the instance can be increased by up to six times the default bandwidth of the instance type, with a maximum increment of 192 MB/s. You can also refer to the prompt information in the current dialog box.
      	Observation Window	Select the length of the observation window. Unit: minutes. Note If the average usage of bandwidth within the observation window is greater than or equal to the threshold, automatic bandwidth increase is triggered.
      Auto Bandwidth Decrease	Auto Bandwidth Decrease	Select the check box to enable the feature. To enable this feature, you must first enable Auto Bandwidth Increase.
      	Average Bandwidth Usage Not Greater Than	The decrease threshold. Select the average bandwidth usage threshold that triggers automatic bandwidth decrease. Unit: %. Valid values: 10% to 70%. The value must be at least 10% lower than the increase threshold. Note The system uses the larger value between the inbound traffic and outbound traffic average usage as the Average Bandwidth Usage.

5. Click OK.

   In the Tair console, the Bandwidth Auto Scaling switch is turned on, indicating that the feature is enabled.

6. Optional: Configure alerts to stay informed about automatic bandwidth increases or decreases for your database instance. You can follow the system prompts to configure alerts.

   Note

   • If you have already configured an alert template for the instance, the alert configuration prompt is not displayed.

   • To configure alert templates and rules yourself, see Configure an alert template and Configure alert rules.

   Click to view detailed steps

   1. Select the system-recommended alert template. The system adds the Auto Scaling Event monitoring item.

   2. Select the Alert Contact Group that you want to receive alert notifications.

   3. Click Submit Configuration and confirm the alert configuration in the dialog box that appears.

References

To schedule an upgrade for the bandwidth of a Tair instance, see Schedule temporary bandwidth upgrades for a Tair instance.