New to KubeDB? Please start here.

Memcached Horizontal Scaling

This guide will give an overview on how KubeDB Ops Manager scales up or down of Memcached database for both the number of replicas and shards.

Before You Begin

• You should be familiar with the following KubeDB concepts:
  • Memcached
  • MemcachedOpsRequest

How Horizontal Scaling Process Works

The following diagram shows how KubeDB Ops Manager scales up or down Memcached database components. Open the image in a new tab to see the enlarged version.

  

The updating process consists of the following steps:

1. At first, a user creates a Memcached Custom Resource (CR).

2. KubeDB Community operator watches the Memcached CR.

3. When the operator finds a Memcached CR, it creates required number of PetSets and related necessary stuff like appbinding, services, etc.

4. Then, in order to scale the number of replica for the Memcached database the user creates a MemcachedOpsRequest CR with desired information.

5. KubeDB Enterprise operator watches the MemcachedOpsRequest CR.

6. When it finds a MemcachedOpsRequest CR, it halts the Memcached object which is referred from the MemcachedOpsRequest. So, the KubeDB Community operator doesn’t perform any operations on the Memcached object during the scaling process.

7. Then the Memcached Ops-manager operator will scale the related PetSet Pods to reach the expected number of replicas defined in the MemcachedOpsRequest CR.

8. After the successful scaling the replicas of the related PetSet Pods, the KubeDB Ops-manager operator updates the number of replicas in the Memcached object to reflect the updated state.

9. After successfully updating of Memcached object, the KubeDB Enterprise operator resumes the Memcached object so that the KubeDB Community operator can resume its usual operations.

In the next doc, we are going to show a step-by-step guide on updating of a Memcached database using scale operation.