The RTO is the target time within which a given application must be restored after a disaster occurs.
Typically, the more critical the applications, the lower the RTO.

Oracle Cloud Infrastructure Container Engine for Kubernetes is a fully-managed, scalable, and highly available service that you can use to deploy your containerized applications to the cloud. Use Container Engine for Kubernetes (sometimes abbreviated to just OKE) when your development team wants to reliably build, deploy, and manage cloud-native applications. You specify the computer resources that your applications require, and Container Engine for Kubernetes provisions them on Oracle Cloud Infrastructure in an existing OCI tenancy.

Explanation
Oracle Functions is a fully managed, multi-tenant, highly scalable, on-demand, Functions-as-a-Service platform. It is built on enterprise-grade Oracle Cloud Infrastructure and powered by the Fn Project open source engine. Use Oracle Functions (sometimes abbreviated to just Functions) when you want to focus on writing code to meet business needs.
The serverless and elastic architecture of OracleFunctions means there's no infrastructure administration or software administration for you to perform. You don't provision or maintain compute instances, and operating system software patches and upgrades are applied automatically. Oracle Functions simplyensures your app is highly-available, scalable, secure, and monitored. With Oracle Functions, you can write code in Java, Python, Node, Go, and Ruby (and for advanced use cases, bring your own Dockerfile, and Graal VM). You can then deploy your code, callit directly or trigger it in response to events, and get billed only for the resources consumed during the execution.

Reference: https://www.youtube.com/watch?v=-
RGzG3F9G_s&list=PLKCk3OyNwIzuHYigVbdtDOZOfChcotfj2&index=10