In https://github.com/3scale/3scale-operator/pull/109 it was requested by Jeff Bride the ability to be able to set resource limits at the DeploymentConfig level.
Currently we provide the ability to disable the resource limits and requests globally and to enable them using specific default values that were calculated to be the best resource/efficiency tradeoff.

He is interested in being able to override limits for some of them, specifically for the Redis databases in his specific use case.

Quoting him:

In summary, I'm of the opinion that it is important that the operator :
1) set default limits and requests in all Deployments
2) allow for over-riding of limits on a select few Deployments, in particular the redis Deployments.

What we were recommending for existing environments is:

• It's important to specify requests and limits in the deployments we expect to be used for production and where we want to ensure resources in order to be able to guarantee performance.
• In other deployments, it's important NOT to specify requests in particular (and they were removed due to popular demand from SAs etc) as people want to be able to do sample/poc/demo/eval deployments of 3scale in low resource environments - and with requests in place, it doesn't even deploy.

The need to do what it has been proposed seems to be related to LimitRanges and Quotas (see the linked PR). Before deciding to apply this we should try to reproduce the issue with LimitRanges/Quotas and see in what those fields affect to the resource limit/requests. More information from their side might be needed