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GPU

GPU Sharing Strategies in Kubernetes

In the previous blogs, we discussed why GPUs are managed differently in Kubernetes and how the GPU Operator can help streamline management. In Kubernetes, although you can request fractional CPU units for workloads, you cannot request fractional GPU units.

Pod manifests must request GPU resources in integers which results in an entire physical GPU allocated to one container even if the container only requires a fraction of the resources. In this blog, we will describe two popular and commonly used strategies to share a GPU on Kubernetes.

Why do we need a GPU Operator for Kubernetes

This is a follow up from the previous blog where we discussed device plugins for GPUs in Kubernetes. We reviewed why the Nvidia device plugin was necessary for GPU support in Kubernetes. A GPU Operator is needed in Kubernetes to automate and simplify the management of GPUs for workloads running on Kubernetes.

In this blog, we will look at how a GPU operator helps automate and streamline operations through the lens of a market leading implementation by Nvidia.

Without and With GPU Operator

Using GPUs in Kubernetes

Unlike CPU and Memory, GPUs are not natively supported in Kubernetes. Kubernetes manages CPU and memory natively. This means it can automatically schedule containers based on these resources, allocates them to Pods, and handles resource isolation and over-subscription.

GPUs are considered specialized hardware and require the use of device plugins to support GPUs in Kubernetes. Device Plugins help make Kubernetes GPU-aware allowing it to Discover, Allocate and Schedule GPUs for containerized workloads. Without a device plugin, Kubernetes is unaware of the GPUs available on the nodes and cannot assign them to Pods. In this blog, we will discuss why GPUs are not natively supported and understand how device plugins help address this gap.

Device Plugin K8s

GPU Metrics - SM Clock

In the previous blog, we discussed why tracking and reporting GPU Memory Utilization metrics matters. In this blog, we will dive deeper into another critical GPU metric i.e. GPU SM Clock. The GPU SM clock (Streaming Multiprocessor clock) metric refers to the clock speed at which the GPU's cores (SMs) are running.

The SM is the main processing unit of the GPU, responsible for executing compute tasks such as deep learning operations, simulations, and graphics rendering. Monitoring the SM clock speed can help users assess the performance and health of your GPU during workloads and detect potential bottlenecks related to clock speed throttling.

GPU SM Clock

Important

Navigate to documentation for Rafay's integrated capabilities for Multi Cluster GPU Metrics Aggregation & Visualization.

GPU Metrics - Memory Utilization

In the introductory blog on GPU metrics, we discussed about the GPU metrics that matter and why they matter. In this blog, we will dive deeper into one of the critical GPU metrics i.e. GPU Memory Utilization.

GPU memory utilization refers to the percentage of the GPU’s dedicated memory (i.e. framebuffer) that is currently in use. It measures how much of the available GPU memory is occupied by data such as models, textures, tensors, or intermediate results during computation.

GPU Memory Utilization

Important

Navigate to documentation for Rafay's integrated capabilities for Multi Cluster GPU Metrics Aggregation & Visualization.

What GPU Metrics to Monitor and Why?

With the increasing reliance on GPUs for compute-intensive tasks such as machine learning, deep learning, data processing, and rendering, both infrastructure administrators and users of GPUs (i.e. data scientists, ML engineers and GenAI app developers) require timely access and insights into performance, efficiency, and overall health of their GPU resources.

In order to make data driven, logical decisions, it is critical for these users to have access to critical metrics for their GPUs. This is the first blog in a series where we will describe the GPU metrics that you should track and monitor. In subsequent blogs, we will do a deep dive into each metric, why it matters and how to use it effectively.

Intro to GPU Metrics

Important

Navigate to documentation for Rafay's integrated capabilities for Multi Cluster GPU Metrics Aggregation & Visualization.