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PostHeaderIcon [VoxxedDaysBucharest2026] Optimizing LLM Inference on Kubernetes: Abdel Sghiouar on Practical Techniques for the Rest of Us

Lecturer

Abdel Sghiouar is a Developer Advocate at Google Cloud with deep expertise in cloud-native technologies, Kubernetes orchestration, and AI/ML workload optimization. Drawing from a robust background in infrastructure engineering and open source contributions, Abdel helps organizations design, deploy, and tune complex AI applications for production environments across diverse infrastructures.

Abstract

While major cloud providers and hyperscalers leverage virtually unlimited computational resources, the majority of organizations face significant constraints when operationalizing Large Language Models. Abdel Sghiouar presents a comprehensive set of practical strategies for optimizing LLM inference workloads on Kubernetes. The session systematically addresses container and model optimization techniques, accelerator management, data persistence and storage considerations, networking and intelligent load balancing, and advanced observability practices. Emphasis is placed on open-source tools and architectural patterns that deliver meaningful cost-performance improvements adaptable to on-premises, hybrid, and public cloud deployments.

Understanding LLM Inference Characteristics and Challenges

Large Language Models continue their rapid evolution in both scale and sophistication. Architectural innovations such as mixture-of-experts (MoE) enable dynamic activation of specialized sub-networks, while multi-modal capabilities process diverse inputs including text, images, audio, and video. Expanded context windows support richer interactions but demand substantial memory resources.

Inference execution comprises two primary phases with contrasting characteristics: the prefill stage (encoding input tokens, predominantly compute-bound) and the decode stage (token generation, typically memory-bound). KV (key-value) caching optimizes conversational flows by preserving intermediate states, avoiding redundant prefill computations for subsequent messages.

Deployment topologies vary considerably. Single-host single-accelerator setups predominate for local development and experimentation (e.g., using Ollama). Single-host multi-accelerator configurations require model sharding across GPUs within one machine. Multi-host distributed deployments introduce complex requirements for high-bandwidth, low-latency interconnects to maintain coherent context across nodes. Each topology presents distinct challenges regarding scalability, fault tolerance, and operational complexity.

Container, Model, and Storage Optimizations

Inference serving runtimes and model artifacts generate exceptionally large container images, frequently exceeding several gigabytes prior to incorporating weights. Conventional optimization strategies like multi-stage builds or native compilation (e.g., GraalVM) prove inadequate for these workloads.

Distributed caching solutions such as Spiegel provide cluster-wide image and model artifact caching, substantially reducing repeated pulls from external registries. Kubernetes-native features enabling containers as volumes allow separate packaging of models, which can then be mounted efficiently onto serving runtimes. When combined with caching layers, these approaches dramatically accelerate cold starts.

Quantization techniques offer another lever, reducing numerical precision (e.g., FP16 to INT8 or lower) to decrease memory footprints while preserving sufficient accuracy for many applications. Careful selection of quantization levels based on task sensitivity balances performance and quality.

Accelerator Management and Dynamic Resource Allocation

Kubernetes has supported GPU scheduling through device plugins for several years. However, static device configurations struggle with real-world constraints including accelerator scarcity and heterogeneous hardware fleets.

Dynamic Resource Allocation, matured in recent Kubernetes versions, introduces flexible resource claiming based on abstract characteristics rather than rigid device specifications (e.g., requesting “NVIDIA GPU with minimum 30GB memory and specific core count”). This enables more efficient scheduling across mixed clusters and better utilization rates.

Integration with cluster autoscalers allows on-demand provisioning, addressing both availability gaps and cost optimization by scaling resources precisely to workload demands. Platform operators describe device inventories; application teams specify requirements, with the scheduler performing intelligent matching.

Networking, Load Balancing, and Observability Considerations

LLM traffic profiles differ markedly from conventional web workloads. Requests exhibit high variability in size and computational intensity (simple text queries versus multi-modal inputs), while responses frequently involve streaming token generation. Standard round-robin load balancing produces inefficient distributions, with certain backends becoming overloaded while others remain underutilized.

The Kubernetes Gateway API, augmented with custom endpoint selection logic, supports sophisticated routing decisions based on request attributes extracted from bodies (model identifier, input modality, streaming requirements) combined with real-time backend telemetry. This facilitates intelligent traffic steering, prioritization of business-critical workloads, and maintenance of sticky sessions necessary for coherent streaming interactions.

Comprehensive observability must encompass prefill and decode phase latencies, KV cache hit rates, token generation throughput, GPU utilization, and end-to-end request metrics. Integration with Prometheus, Grafana, and specialized LLM monitoring solutions provides actionable insights for capacity planning and bottleneck identification.

Practical Patterns and the LLM-D Project

The LLM-D initiative, hosted under the Linux Foundation with contributions from Google, IBM, NVIDIA, and additional partners, aggregates architectural patterns, performance benchmarks, and reference implementations for production-grade inference. Key elements include optimized prefill/decode separation, advanced routing logic often leveraging engines like vLLM, and comprehensive guidance for multi-node deployments.

A holistic, layered optimization strategy proves most effective: infrastructure-level improvements (caching, persistent volumes), platform capabilities (dynamic scheduling, intelligent networking), and application-level choices (model quantization, serving engine selection). Organizations without hyperscale resources can still achieve competitive efficiency and scalability through disciplined application of these patterns.

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PostHeaderIcon [DevoxxGR2026] GenAI on Kubernetes: Training, Inference, and Serving in Production Environments

Lecturer
Alessandro Vozza is a seasoned cloud-native advocate and technologist with deep expertise in Kubernetes and AI/ML operations. He contributes actively to open-source communities and focuses on practical, scalable deployments of generative AI workloads. As a speaker and practitioner, Alessandro emphasizes operational excellence, resource efficiency, and the integration of modern AI tools within established cloud-native platforms.

Abstract
In this hands-on tutorial at Devoxx Greece 2026, Alessandro Vozza guides developers through the complete lifecycle of running generative AI workloads on Kubernetes. From distributed training jobs with GPU scheduling to optimized inference and scalable model serving, the session demonstrates how to leverage operators, autoscaling, vector stores, and frameworks like KServe, Ray, vLLM, and Kubeflow. Attendees gain actionable insights into designing efficient GPU clusters, fine-tuning models securely, and deploying production-grade architectures that integrate seamlessly with existing Kubernetes expertise.

The Convergence of Kubernetes and Generative AI

Kubernetes has evolved into the de facto platform for orchestrating complex, resource-intensive workloads, including those powered by generative AI. Vozza begins by contextualizing the challenges: training large models demands massive parallel computation across GPUs, inference requires low-latency serving under variable traffic, and the entire pipeline must remain observable, secure, and cost-effective. Traditional approaches struggle with these demands, but Kubernetes patterns—scheduling, autoscaling, and declarative resource management—provide a robust foundation.

The session highlights how the community has responded with specialized tools. Projects like Kubeflow address the full ML lifecycle, while KServe and vLLM focus on high-performance inference. These build upon core Kubernetes capabilities, allowing teams to treat AI workloads with the same rigor applied to microservices.

Distributed Training and GPU Orchestration

Training generative models is computationally intensive and benefits enormously from Kubernetes’ scheduling strengths. Vozza demonstrates launching distributed training jobs, emphasizing GPU-aware scheduling through device plugins and resource requests. Nodes are labeled with GPU capacity, enabling the scheduler to place pods on suitable hardware.

The tutorial covers hyperparameter tuning with tools like Katib, which automates experimentation across multiple configurations. Fine-tuning involves augmenting base models with domain-specific data, a process that Kubernetes orchestrates reliably through persistent volumes and checkpointing. Attendees learn to monitor training progress using built-in observability and handle failures gracefully with retries and job controllers.

Resource efficiency emerges as a key theme. Techniques such as multi-instance GPU (MIG) partitioning allow a single physical GPU to support multiple smaller workloads, maximizing utilization without over-provisioning expensive hardware.

Inference Serving and Model Deployment

Once trained, models must be served efficiently. Vozza walks through deploying inference endpoints with KServe, which abstracts the complexities of scaling and routing. vLLM serves as the high-throughput inference engine, leveraging continuous batching and paged attention for superior performance.

The architecture supports multi-model serving, where a single deployment handles various models based on request characteristics. Gateway API extensions make the ingress layer LLM-aware, enabling intelligent routing based on factors like key-value cache state or model specialization. This ensures optimal resource allocation and minimal latency.

Autoscaling plays a critical role. Horizontal Pod Autoscaler (HPA) combined with KEDA reacts to custom metrics such as queue depth or tokens processed per second, dynamically adjusting replicas to match demand while controlling costs.

Operational Considerations and Best Practices

Production readiness demands comprehensive observability. Vozza integrates Prometheus exporters and logging to track token throughput, latency, and GPU utilization. Security best practices include least-privilege access for model endpoints and encrypted communication.

The tutorial addresses common pitfalls: managing model registries for versioning, handling cold starts through caching, and ensuring reproducibility across environments. By treating models as first-class Kubernetes citizens, teams achieve consistent deployments from development to production.

Practical Roadmap and Future Directions

Participants receive a working reference setup they can adapt immediately. Vozza encourages starting small—perhaps with a single-model inference service—before scaling to distributed training and multi-model architectures. The session reinforces that Kubernetes knowledge directly transfers to AI operations, lowering the barrier for traditional platform teams.

Looking ahead, evolving features like dynamic resource allocation and improved GPU topology awareness will further streamline GenAI workloads. The message is clear: Kubernetes is not merely compatible with generative AI; it is becoming the preferred operational layer for the entire lifecycle.

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