Epic Goal*

Provide a way to change the etcd database size limit from the default 8GB which is non-configurable.
https://etcd.io/docs/v3.5/dev-guide/limit/#storage-size-limit

https://github.com/openshift/cluster-etcd-operator/blob/dbfa8262a0a48846e8519425a937a7d4e9fd52e0/pkg/etcdenvvar/etcd_env.go#L42

This will likely be done through the API as a new field in the `cluster` `etcds.operator.openshift.io` CustomResouce object. Similar to the etcd latency tuning profiles which allow a selectable set of configurations this limit should also be bound within reasonable limits or levels.

 
Why is this important? (mandatory)

Due to historical reasons, the etcd operator uses a static definition of an 8GB limit. Nowadays, customers with dense cluster configurations regularly reach the limit. OpenShift should provide a mechanism for increasing the database size while maintaining a validated configuration.

The 8GB limit was due to historical limitations of the bbolt store which have been improved upon for a while and there are examples and discussion upstream to suggest that the quota limit can be set higher.

See:

• https://github.com/etcd-io/website/issues/588
• https://github.com/etcd-io/etcd/issues/15354
• https://github.com/etcd-io/etcd/issues/12690
• https://github.com/etcd-io/etcd/issues/9771

Scenarios (mandatory) 

Provide details for user scenarios including actions to be performed, platform specifications, and user personas.  

1. As an admin I can increase the etcd database size via the openshift etcd API

 
Dependencies (internal and external) (mandatory)

What items must be delivered by other teams/groups to enable delivery of this epic. 

Contributing Teams(and contacts) (mandatory) 

Our expectation is that teams would modify the list below to fit the epic. Some epics may not need all the default groups but what is included here should accurately reflect who will be involved in delivering the epic.

• Development - etcd team
• Documentation - etcd docs team
• QE - 
• PX - 
• Others -

Acceptance Criteria (optional)

Provide some (testable) examples of how we will know if we have achieved the epic goal.  

Drawbacks or Risk (optional)

Reasons we should consider NOT doing this such as: limited audience for the feature, feature will be superseded by other work that is planned, resulting feature will introduce substantial administrative complexity or user confusion, etc.

Done - Checklist (mandatory)

The following points apply to all epics and are what the OpenShift team believes are the minimum set of criteria that epics should meet for us to consider them potentially shippable. We request that epic owners modify this list to reflect the work to be completed in order to produce something that is potentially shippable.

• CI Testing -  Basic e2e automationTests are merged and completing successfully
• Documentation - Content development is complete.
• QE - Test scenarios are written and executed successfully.
• Technical Enablement - Slides are complete (if requested by PLM)
• Engineering Stories Merged
• All associated work items with the Epic are closed
• Epic status should be “Release Pending”