Grafana Mimir 3.0 introduces significant performance improvements, including a new query engine and a decoupled architecture to better handle read and write operations. These changes enhance reliability, reduce resource usage, and optimize costs for large-scale deployments. Upgrading requires careful planning due to the architectural shifts.

Grafana Mimir can be effectively deployed on bare metal or virtual machines instead of Kubernetes, especially when Kubernetes is unavailable or to avoid circular dependencies in metrics management. Additionally, running Mimir outside of Kubernetes can provide valuable learning experiences about the software. Factors such as resource allocation, flexibility, and management complexity should be considered when choosing the deployment method.