Inspections and recommendations in Yandex Managed Service for Valkey™

Managed database clusters regularly undergo diagnostics to detect possible issues, increase the cluster's reliability, and improve its performance. The results of such checks are displayed as inspections under Recommendations. You can see notifications about successful checks and recommendations on eliminating discovered risks. The responsibility to troubleshoot any detected issues lies within the Yandex Cloud user's remit.

All checks have a severity level:

• High level: Criteria of high cluster availability, significant risks of reduced performance, data loss risks. Such checks warrant special attention and require following the recommendations provided.
• Moderate level: Possible risks of reduced performance, suboptimal memory and disk space usage.
• Low level: Potential risks and cluster operation limitations.

The list of recommendations is updated regularly. For each recommendation, the following timestamps are fixed: the date of the risk's first detection and the date of the most recent status update on this issue. If the recommendation seems to be excessive or incorrect, you can hide it, specifying a reason. Once the hiding period expires, the recommendation will automatically become available again if the issue persists.

Recommendations are available at the cluster, folder, and cloud levels and provide tips for all your resources. However, the absence of recommendations does not mean that your cluster is optimized: the list of checks gets continuously appended but still remains incomprehensive and cannot replace monitoring, since it is targeted at detecting patterns rather than specific issues. You can additionally run cluster performance diagnostics and analyze monitoring metrics.

Managing recommendations in Yandex Managed Service for Valkey™ requires the managed-redis.editor role or higher.

Available inspections in Yandex Managed Service for Valkey™Available inspections in Yandex Managed Service for Valkey™

Category	Check	Risk	Severity
Performance	CPU usage (main thread)	Risk of reduced performance	Moderate
Performance	Cache hit rate	Low cache hit rate	Moderate
High availability	Availability of replicas in a shard	Risk of data loss and cluster unavailability in the event of a zone failure (lack of replicas)	Low
High availability	High cluster availability during zone failure	Risk of data loss and cluster unavailability in the event of a zone failure	High
High availability	Memory allocation	Lack of RAM	Moderate
High availability	Database version updates	Database version is out of date	High
High availability	Valkey™ memory usage policy	The memory usage limit has been reached on the host	Moderate
High availability	Disk autoscaling feature	Disk space autoscaling is limited	Moderate

Risk of reduced performanceRisk of reduced performance

Description

The host continuously uses all CPU resources in main thread, which may cause delays in query processing. Check the load and optimize your queries, including those sent via the AI assistant, or increase the computing resources allocated to your cluster.

Action

To increase the cluster computing resources:

1. Navigate to Yandex Managed Service for Valkey™.
2. Select your cluster and click Edit.
3. Under Resources, select a host class with the required amount of vCPUs.
4. Click Save changes.

Low cache hit rateLow cache hit rate

Description

A low cache hit rate has been detected. Check the load and optimize your queries or increase the amount the cluster's RAM.

Action

To update host resources:

1. Navigate to Yandex Managed Service for Valkey™.
2. Select your cluster and click Edit.
3. Under Host compute resources, select a host class with the required amount of RAM.
4. Click Save changes.

Risk of data loss and cluster unavailability in the event of a zone (replica) failureRisk of data loss and cluster unavailability in the event of a zone (replica) failure

Description

Your shards have no replicas, posing a risk of data loss and cluster unavailability. For high availability, make sure the specified shards have replicas in another zone.

Action

To add a host to a different zone:

1. Navigate to Yandex Managed Service for Valkey™.
2. Select the cluster and open the Hosts tab.
3. Click Create host.
4. In the host settings, specify an alternative availability zone.
5. Finish configuring the host and click Save.

Risk of data loss and cluster unavailability in the event of a zone failureRisk of data loss and cluster unavailability in the event of a zone failure

Description

The current distribution of cluster hosts does not ensure fault protection in a single availability zone. Put replicas in different zones to ensure high availability.

Action

To migrate hosts from one availability zone to another, add hosts in the target availability zone to the cluster and delete hosts from the source availability zone:

1. Create a subnet in the target availability zone for the hosts.

2. If your cluster uses the b2.medium or b3-c1-m4 host class, change it. Otherwise, you will not be able to add hosts to the cluster and perform migration.

   The cluster is unavailable for about five to seven minutes after changing the host class.

   You can revert to the previous host class after the migration is complete.

3. Add a host to your cluster: Navigate to Yandex Managed Service for Valkey™.

4. Click the name of your cluster and select the Hosts tab.

5. Click Create host.

6. Specify the following host settings:

   • Target availability zone for your hosts.
   • New subnet.
   • To make the host accessible from outside Yandex Cloud, select Public access.

7. Click Save.

8. Delete the hosts in the source availability zone.

Not enough RAMNot enough RAM

Description

The cluster is running out of RAM, which causes freezes or emergency stops. Increase the cluster's RAM.

Action

To increase the amount of RAM:

1. Navigate to Yandex Managed Service for Valkey™.
2. Select your cluster and click Edit.
3. Under Resources, select a host class with the required amount of RAM.
4. Click Save changes.

Database version is out of dateDatabase version is out of date

Description

The database version is out of date. Support for the version was officially discontinued. Clusters are running, but support is limited. We recommend upgrading to a supported version.

Action

To upgrade the database version:

1. In the management console, navigate to the folder page.
2. Navigate to Yandex Managed Service for Valkey™.
3. Select the cluster and click Edit.
4. In the Version field, select the Valkey™ version you need.
5. Click Save.

For more information about supported database versions, see Database version control policy.

The memory usage limit has been reached on the hostThe memory usage limit has been reached on the host

Description

The memory usage limit has been reached on the host. The noeviction policy does not allow new inserts without data deletion. To resolve the issue, do one of the following: delete unused data, modify the memory usage policy in cluster settings, or increase the available memory.

Action

You can modify the memory policy or increase the amount of memory:

1. Navigate to Yandex Managed Service for Valkey™.

2. Select the cluster.

3. At the top of the page, click Edit.

   • To modify the memory policy in the DBMS settings, provide a value for Maxmemory policy.
   • To increase the amount of memory, set a new value in the cluster resource settings.

Disk space autoscaling is limitedDisk space autoscaling is limited

Description

The disk autoscaling limit has been reached, so the cluster cannot increase its disk space when needed. Change the autoscaling settings in the cluster and increase the limit.

Action

To increase the disk size:

1. Navigate to Yandex Managed Service for Valkey™.
2. Select your cluster and click Edit.
3. Specify the maximum storage size after the expansion in the Maximum storage size field.
4. Click Save changes.