Comprehensive guide to different types of virtual machines in cloud computing including shared VMs transient VMs and reserved instances with their use cases and benefits
Cloud providers offer various types of virtual machines to meet different workload requirements, including shared VMs for cost efficiency, dedicated VMs for performance, reserved instances for predictable workloads, and transient VMs for fault-tolerant applications, each with unique pricing models and use cases.
This documents explains the different types of virtual machines available in the cloud. Machines, also known as Virtual Servers or Virtual Instances, are available in various configurations and deployment options to serve different use cases. When creating a virtual server in the cloud, you specify the Region and Zone or Data Center for provisioning and the desired Operating System. You can choose between shared (multi-tenant) VMs or dedicated (single-tenant) VMs, and select billing options (hourly or monthly), storage, and networking options.
Virtual Machines, also known as Virtual Servers or Virtual Instances, are available in various configurations and deployment options to serve different use cases. When creating a virtual server in the cloud, you specify the Region and Zone or Data Center for provisioning and the desired Operating System. You can choose between shared (multi-tenant) VMs or dedicated (single-tenant) VMs, and select billing options (hourly or monthly), storage, and networking options.
Shared or Public Cloud VMs are provider-managed, multi-tenant deployments that can be provisioned on-demand with predefined sizes. The underlying physical server is virtualized and shared across multiple tenants or users. Cloud providers offer configurations for different workloads, such as Compute Intensive, Memory Intensive, or High Performance I/O. Some providers also offer custom configurations. Public VMs are usually priced by the hour, with some providers offering monthly VMs for cost savings.
Transient or Spot VMs take advantage of unused capacity in a cloud data center, available at a lower cost than regular VMs. However, the cloud provider can de-provision these VMs at any time. These VMs are ideal for non-production workloads, such as testing and developing applications, running stateless workloads, testing scalability, or running big data and high performance computing (HPC) workloads at a low cost.
Reserved virtual server instances allow you to reserve capacity and guarantee resources for future deployments. You can reserve the desired amount of virtual server capacity, provision instances when needed, and choose a term (e.g., 1 year or 3 years). This guarantees capacity within the data center for the contract term and can lower costs compared to hourly or monthly instances. Reserved capacity is useful when you need a certain level of cloud capacity for a specific duration. Note that not all predefined VM families or configurations may be available as reserved.
Dedicated hosts offer single-tenant isolation, meaning only your VMs run on a given host, making exclusive use of the underlying hardware’s full capacity and resources. When provisioning a dedicated host, you specify the data center and POD for placement and assign instances to a specific host. This allows for maximum control over workload placement and is typically used for meeting compliance and regulatory requirements or specific licensing terms.
| VM Type | Description | Use Cases | Billing | Isolation | Control |
|---|---|---|---|---|---|
| Shared VMs | Multi-tenant, on-demand, predefined sizes | General-purpose computing | Hourly or Monthly | Shared | Provider-managed |
| Transient VMs | Low-cost, de-provisioned at any time | Non-production workloads, testing, HPC | Hourly | Shared | Provider-managed |
| Reserved Instances | Reserved capacity, guaranteed resources | Long-term deployments, cost savings | Monthly or Term | Shared | User-managed |
| Dedicated Hosts | Single-tenant isolation, full hardware capacity | Compliance, licensing, control | Monthly | Shared | User-managed |
Understanding the different types of virtual machines available in the cloud is essential for selecting the right deployment option for your workloads. Whether you need shared VMs for general-purpose computing, transient VMs for cost-effective workloads, reserved instances for guaranteed capacity, or dedicated hosts for compliance and control, cloud providers offer a range of options to meet your requirements. By choosing the right VM type, you can optimize performance, cost, and resource utilization for your cloud-based applications and services.