QONNECT: QoS-Aware Orchestration for Distributed Kubernetes Clusters

Introduction

Running across multiple Kubernetes (and K3s) clusters is easy to start and hard to operate. The moment you care about latency, cost, availability, or locality, you’re no longer “just deploying”—you’re continuously trading off placement decisions as conditions change.

QONNECT, presented in October 2024, is a QoS-aware orchestration system designed for distributed clusters. It aims to make those trade-offs explicit by letting you express high-level QoS goals and then translating them into concrete placement and migration actions across heterogeneous Kubernetes and K3s environments.

When people say “QoS” here, it typically means goals like:

• keeping user-facing traffic within a latency envelope,
• preferring locality (edge-first) unless capacity is constrained,
• balancing cost against performance for bursty workloads.

QoS-Aware Orchestration

• QoS goals enable specification of high-level quality of service requirements.
• Automatic placement translates QoS goals into optimal resource placement.
• Migration capabilities enable automatic migration of workloads based on QoS requirements.
• Multi-cluster support enables QoS-aware orchestration across multiple clusters.

Distributed Architecture

1. Knowledge Base provides centralized knowledge management for orchestration decisions.
2. Resource Lead Agents use Raft replication for consistent decision-making.
3. Resource Agents provide lightweight agents in each cluster for local operations.
4. Coordination enables seamless coordination across distributed components.

Orchestration Capabilities

• Placement optimization enables optimal placement of workloads based on QoS requirements.
• Migration automation enables automatic migration of workloads when QoS requirements change.
• Failover capabilities enable automatic failover based on QoS requirements.
• Scaling optimization enables QoS-aware scaling of workloads.

Use Cases

• Multi-cluster deployments enable QoS-aware deployment across multiple clusters.
• Edge computing enables QoS-aware deployment to edge locations.
• Hybrid cloud enables QoS-aware deployment across on-premises and cloud.
• Cost optimization enables cost-aware placement based on QoS requirements.

Practical notes (distributed QoS is never “set and forget”)

• Define what you can measure: QoS goals work best when they map to observable signals (latency, error rate, resource saturation), not vague intent.
• Beware migration thrash: frequent migrations can hurt more than they help; introduce hysteresis and guardrails where possible.
• Heterogeneity matters: Kubernetes vs K3s, different hardware, and different network paths can make “equivalent” clusters behave very differently under the same policy.

Summary

QONNECT represents a significant advancement in QoS-aware orchestration, providing teams with powerful capabilities for managing applications across distributed Kubernetes clusters.