Flavor Features and Restrictions

Flavors in Hyperstack include specific labels that define their features, restrictions, and suitability for various use cases. These labels outline the capabilities and limitations of each flavor, making it essential to understand them when choosing the right flavor for your requirements.

In this article

• Flavor features
  • Network optimization
  • Hibernation
  • Snapshots
  • Bootable from volume

Flavor features

The capabilities, limitations, and suitability of flavors for different use cases depend on the GPU/CPU type. The table below outlines the features and limitations of each available flavor.

Flavor	Network Optimized	Hibernation	Snapshots	Bootable from volume
H100 80GB PCIe	✅	✅	✅	✅
H100 80G PCIe w/ NVLink	✅	✅	✅	✅
H100 80G SXM5 - CANADA-1	✅	✅	✅	✅
H100 80G SXM5 - US-1	✅	❌	❌	❌
A100 80G PCIe	❌	✅	✅	✅
A100 80G PCIe w/ NVLink	✅	✅	✅	✅
L40	❌	✅	✅	✅
RTX A6000	❌	✅	✅	✅
RTX A4000	❌	❌	❌	❌
CPU Only - NORWAY-1	❌	❌	❌	❌
CPU Only - CANADA-1	❌	❌	❌	✅
CPU Only xlarge & xxlarge - CANADA-1	✅	❌	❌	✅

Network optimization

For workloads requiring higher bandwidth between virtual machines, known as inter-VM bandwidth, Hyperstack offers select flavors featuring high-speed networking powered by SR-IOV (Single Root I/O Virtualization) technology, known as network optimized flavors. SR-IOV enables a single physical network interface to be shared among multiple VMs, supporting inter-VM bandwidth of up to 350 Gbps.

To learn more about high-speed networking with Hyperstack, click here.

Flavor label

• network_optimised: This flavor label indicates that the flavor is network optimized and will provide enhanced inter-VM networking speeds.

Limitations

• Limited networking speeds: Flavors without network optimization will have slower inter-VM bandwidth speeds.

Hibernation

Hyperstack provides a variety of flavors that support hibernation, enabling you to preserve the current state of a virtual machine (VM) by saving it to disk for future restoration. During hibernation, the VM's configuration and root disk data are saved, allowing for quick resumption without requiring a full boot sequence.

Flavor label

• no-hibernation: Flavors with this label do not support hibernation, typically due to limitations in the underlying hardware or virtualization technology that prevent saving and restoring VM states. To use hibernation, choose a flavor that does not have the no-hibernation label.

Limitations

• Resource consumption: For flavors without hibernation, virtual machines must either remain running, be completely shut down, or be deleted. There is no option to temporarily save the machine state while reducing resource usage.

• Startup time: Hibernation enables faster startup times by allowing the VM to resume from a saved state. Without hibernation, VMs must perform a full boot sequence after being powered off.

Snapshots

Hyperstack offers a range of flavors that support snapshots, allowing you to capture the VM's system state at a specific point in time by saving its configuration and bootable volume data to disk for future restoration.

Flavor label

• no-snapshot: Flavors with this label do not support snapshot creation, due to technical limitations or performance considerations. As a result, you cannot capture the current state of the virtual machine for backup or cloning. To use snapshots, select flavors without this label that meet the requirements of your workload.

Limitations

• Backup limitations: Without snapshot support, you cannot create point-in-time backups of your virtual machine. Consider implementing alternative backup strategies, such as application-level backups or external data replication.

• Cloning restrictions: Snapshots are often used as a baseline for cloning virtual machines. Flavors with no-snapshot cannot be cloned using snapshot-based methods.

Bootable from volume

Bootable volumes contain all the essential files, configurations, and settings required to run a virtual machine's operating system. Hyperstack provides a variety of flavors that can be deployed using a bootable volume. Flavors labeled "Local Storage Only" do not support booting from volumes. Learn more about this restriction below.

Flavor label

• local-storage-only: Flavors with this label are limited to using local hypervisor storage for the boot process and cannot boot from Ceph or shared storage volumes. This restriction ensures optimal performance or compatibility with specific workloads. However, you can still attach non-bootable volumes to the VM after deployment.

Limitations

• Boot restrictions: VMs with this label cannot boot from shared storage like Ceph. They must use local hypervisor storage for the boot process.

• Volume attachment: Non-bootable volumes can still be attached to the VM after deployment.

• Error handling: If a user attempts to boot from a volume with a flavor labeled local-storage-only, an error message will be displayed stating: "Boot from Volume Not Possible for this flavor."

• UI messaging: The Deploy VM page will display a message: "The flavor type doesn’t allow boot from volume. Learn More" with a link to additional documentation explaining the restriction.

• Live documentation: A dynamic document will list all flavors restricted to local storage for easy reference.