Azure Virtual Machines

Compute Options for Azure Virtual Machines

This document outlines the various compute options available when deploying and managing Azure Virtual Machines (VMs). Choosing the right compute option is crucial for optimizing performance, cost, and scalability for your specific workloads.

1. VM Sizes and Series

Azure offers a wide range of VM sizes, categorized into different series, each optimized for specific workload types:

  • General Purpose (A, B, D, E series): Balanced CPU-to-memory ratio, suitable for development, testing, small to medium databases, and web servers.
  • Compute Optimized (F series): High CPU-to-memory ratio, ideal for high-performance web servers, batch processes, application servers, and gaming servers.
  • Memory Optimized (G, M, N series): High memory-to-CPU ratio, designed for relational database servers, large caches, in-memory analytics, and SAP HANA.
  • Storage Optimized (Lsv2, Lsv3 series): High disk throughput and IOPS, suitable for Big Data, NoSQL databases, and data warehousing.
  • GPU Optimized (NC, ND, NV series): VMs with high-performance GPUs for machine learning, deep learning, rendering, and video editing.
  • HPC Optimized (HB, HC series): For High-Performance Computing workloads requiring massive parallel processing power.

You can find a detailed comparison of VM sizes and their specifications in the Azure VM documentation portal.

2. VM Images and Operating Systems

Azure provides a comprehensive library of VM images, including:

  • Windows Server: Latest versions and specific editions.
  • Linux Distributions: Ubuntu, CentOS, Red Hat Enterprise Linux, SUSE Linux Enterprise Server, Debian, and more.
  • Specialized Images: SQL Server pre-installed, SAP certified images, and other marketplace solutions.

You can also create and deploy custom VM images from your own virtual hard disks (VHDs).

3. Azure Compute Gallery

The Azure Compute Gallery (formerly Shared Image Gallery) is a service for managing and sharing VM images across your Azure subscriptions and regions. It simplifies image management and deployment consistency.

Note: Utilizing Azure Compute Gallery is recommended for managing your custom VM images effectively.

4. Spot Virtual Machines

Azure Spot Virtual Machines leverage unused Azure capacity at a discounted price. They are ideal for fault-tolerant workloads, batch jobs, rendering, testing, and development environments where interruptions are acceptable.

Spot VMs can be evicted with short notice, so they are not suitable for critical production workloads that require continuous availability.

5. Scale Sets

Virtual Machine Scale Sets (VMSS) allow you to deploy and manage a set of identical, load-balanced VMs. They automatically scale up or down based on demand or a schedule, ensuring high availability and application performance.

Tip: Use VM Scale Sets for web applications, APIs, and other stateless services that need to handle varying traffic loads.

6. Azure Kubernetes Service (AKS)

While not a direct VM compute option in itself, AKS provides a managed Kubernetes service on Azure. It abstracts away much of the underlying VM management, allowing you to focus on container orchestration. AKS uses VMs as its underlying compute infrastructure.

7. Serverless Compute Options (Alternatives)

For certain workloads, serverless compute options might be more suitable than traditional VMs:

  • Azure Functions: For event-driven, small-scale compute.
  • Azure Container Instances (ACI): For running containers without managing VMs.
  • Azure App Service: For hosting web applications, mobile backends, and APIs.

Consider these options if your workload can be containerized or is event-driven.

Understanding these compute options will help you design and deploy efficient, cost-effective, and scalable solutions on Azure Virtual Machines.