Database Autonomy Service (DAS) monitors your Redis cluster instances and automatically adds a shard when average memory utilization crosses a threshold you define. This prevents out-of-memory (OOM) errors during traffic or data-size spikes without requiring manual intervention.
Prerequisites
Before you begin, ensure that you have:
A Redis Open-Source Edition cloud-native instance that uses a cluster architecture
How it works
DAS periodically checks your instance during the configured Observation Window. When the instance's Average Memory Utilization reaches the configured threshold, DAS automatically adds one shard. Adding a shard follows the same billing rules and configuration change process as manually adjusting the shard count for a Redis instance that uses cloud disks. Shard additions stop once the total shard count reaches the configured Maximum Number Of Shards.
Enable automatic shard addition
Log on to the DAS console.
In the left-side navigation pane, choose Intelligent O&M Center > Instance Monitoring.
Find the instance you want to manage and click its instance ID to open the instance details page.
In the left-side navigation pane, click Autonomy Center. In the upper-right corner, click Autonomy Service Settings.
On the Autonomous Function Management > Autonomous Function Settings tab, turn on the autonomy feature switch.
On the Optimization And Throttling tab, select Automatically Add Shards and configure the parameters.
NoteBilling and the configuration change process are the same as for manually adjusting the shard count on a Redis instance that uses cloud disks. For details, see Change instance configurations.
Parameter Description Average Memory Usage ≥ The memory utilization threshold that triggers a shard addition. Maximum Number Of Shards The upper limit on shards for this instance. Must be a positive integer between 4 and 256. DAS stops adding shards automatically when this limit is reached. Observation Window The time range during which DAS observes instance performance. DAS adds a shard when average memory utilization reaches the threshold during this window. Click OK.
Optional: Click Event Subscription Settings and configure event notifications to receive timely notifications of system-triggered operations. For more information, see Enable event subscription.
(Optional) On the Event Subscription Settings tab, set up event notifications for automatic shard additions. When DAS generates a shard addition recommendation, it creates a Notice-level event. Turn on Enable Event Subscription and configure the notification parameters. For details, see Enable the event subscription feature.
You can configure an Alert Template to track the status of shard additions. DAS recommends an alert template and adds alert rules for the corresponding autonomy events. Follow the prompts to complete the configuration.
NoteIf you already have an alert template configured for the instance, follow the prompts to add the autonomy event alert rules to the existing template.
To configure the alert template and rules manually, see Configure alert templates and Configure alert rules.
Select an Alert Contact Group for notifications. For details, see Manage alert contacts.
Click Add Contact to add an alert contact.
Click Create Contact Group to create a new alert contact group.
Click Edit or Remove next to a contact to update or delete it.
Click Submit Configuration and confirm the alert configuration in the dialog box.
References
To reduce the number of shards in a Redis database instance, you must perform the operation manually. For details, see Adjust the number of shards in a cluster.