A set of instance types and preferences to help create KubeVirt VirtualMachines.
The available instance types can be divided into two categories:
- Workload agnostic - or general purpose
- Workload specific
Workload agnostic instance types are a good starting point to run your workload. Once you know more about the requirements of your workload, you can start choosing a workload specific instance type.
The following diagram summarizes the available instance types and their use-cases:
graph TD
classDef grp fill:white,stroke:lightgray,color:gray
classDef series fill:lightyellow,stroke:lightgray
classDef instancetype fill:
wrklda(Workload agnostic)
wrklds(Workload specific)
class wrklda grp
wrklda:::grp --> Universal:::series
Universal([Universal]):::series --> u1:::instancetype
wrklda:::grp --> Overcommitted:::series
Overcommitted([Overcommitted]):::series --> o1:::instancetype
wrklds:::grp --> Computeexclusive:::series
Computeexclusive([Compute Exclusive]):::series --> cx1:::instancetype
wrklds:::grp --> Memory:::series
Memory([Memory]):::series --> m1:::instancetype
wrklds:::grp --> Network:::series
Network([Network]):::series --> n1:::instancetype
wrklds:::grp --> Realtime:::series
Realtime([Realtime]):::series --> rt1:::instancetype
Various labels are used to decorate objects provided by this project to help end users find the right resources for them. See docs/labels.md for more details.
Click in order to view the instance type names schema
instanceTypeName = seriesName , "." , size;
seriesName = ( class | vendorClass ) , version;
class = "u" | "o" | "cx" | "g" | "m" | "n" | "rt";
vendorClass = "g" , vendorHint;
vendorHint = "n" | "i" | "a";
version = "1";
size = "small" | "medium" | "large" | [( "2" | "4" | "8" )] , "xlarge";| . | U | O | CX | M | N | RT |
|---|---|---|---|---|---|---|
| Hugepages | ✓ | ✓ | ✓ | ✓ | ||
| Overcommitted Memory | ✓ | |||||
| Dedicated CPU | ✓ | ✓ | ✓ | |||
| Burstable CPU performance | ✓ | ✓ | ✓ | |||
| Isolated emulator threads | ✓ | ✓ | ✓ | |||
| vNUMA | ✓ | ✓ | ||||
| vCPU-To-Memory Ratio | 1:4 | 1:4 | 1:2 | 1:8 | 1:2 | 1:4 |
The U Series is quite neutral and provides resources for general purpose applications.
U is the abbreviation for "Universal", hinting at the universal attitude towards workloads.
VMs of instance types will share physical CPU cores on a time-slice basis with other VMs.
Specific characteristics of this series are:
- Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
- vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4, for less noise per node.
The O Series is based on the U Series, with the only difference being that memory is overcommitted.
O is the abbreviation for "Overcommitted".
Specific characteristics of this series are:
- Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
- Overcommitted Memory - Memory is over-committed in order to achieve a higher workload density.
- vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4, for less noise per node.
The CX Series provides exclusive compute resources for compute intensive applications.
CX is the abbreviation of "Compute Exclusive".
The exclusive resources are given to the compute threads of the VM. In order to ensure this, some additional cores (depending on the number of disks and NICs) will be requested to offload the IO threading from cores dedicated to the workload. In addition, in this series, the NUMA topology of the used cores is provided to the VM.
Specific characteristics of this series are:
- Hugepages - Hugepages are used in order to improve memory performance.
- Dedicated CPU - Physical cores are exclusively assigned to every vCPU in order to provide fixed and high compute guarantees to the workload.
- Isolated emulator threads - Hypervisor emulator threads are isolated from the vCPUs in order to reduce emaulation related impact on the workload.
- vNUMA - Physical NUMA topology is reflected in the guest in order to optimize guest sided cache utilization.
- vCPU-To-Memory Ratio (1:2) - A vCPU-to-Memory ratio of 1:2.
The M Series provides resources for memory intensive applications.
M is the abbreviation of "Memory".
Specific characteristics of this series are:
- Hugepages - Hugepages are used in order to improve memory performance.
- Burstable CPU performance - The workload has a baseline compute performance but is permitted to burst beyond this baseline, if excess compute resources are available.
- vCPU-To-Memory Ratio (1:8) - A vCPU-to-Memory ratio of 1:8, for much less noise per node.
The N Series provides resources for network intensive DPDK applications, like VNFs.
N is the abbreviation for "Network".
This series of instancetypes requires nodes capable of running DPDK workloads and being marked with the respective node-role.kubevirt.io/worker-dpdk label as such.
Specific characteristics of this series are:
- Hugepages - Hugepages are used in order to improve memory performance.
- Dedicated CPU - Physical cores are exclusively assigned to every vCPU in order to provide fixed and high compute guarantees to the workload.
- Isolated emulator threads - Hypervisor emulator threads are isolated from the vCPUs in order to reduce emaulation related impact on the workload.
- vCPU-To-Memory Ratio (1:2) - A vCPU-to-Memory ratio of 1:2.
The RT Series provides resources for realtime applications, like Oslat.
RT is the abbreviation for "realtime".
This series of instance types requires nodes capable of running realtime applications.
Specific characteristics of this series are:
- Hugepages - Hugepages are used in order to improve memory performance.
- Dedicated CPU - Physical cores are exclusively assigned to every vCPU in order to provide fixed and high compute guarantees to the workload.
- Isolated emulator threads - Hypervisor emulator threads are isolated from the vCPUs in order to reduce emaulation related impact on the workload.
- vCPU-To-Memory Ratio (1:4) - A vCPU-to-Memory ratio of 1:4 starting from the medium size.
To get started with customizing or creating your own instancetypes and preferences see DEVELOPMENT.md.
The following instancetype resources (cluster-wide and namespaced) are provided by this project:
| Name | vCPUs | Memory |
|---|---|---|
| cx1.2xlarge | 8 | 16Gi |
| cx1.4xlarge | 16 | 32Gi |
| cx1.8xlarge | 32 | 64Gi |
| cx1.large | 2 | 4Gi |
| cx1.medium | 1 | 2Gi |
| cx1.xlarge | 4 | 8Gi |
| m1.2xlarge | 8 | 64Gi |
| m1.4xlarge | 16 | 128Gi |
| m1.8xlarge | 32 | 256Gi |
| m1.large | 2 | 16Gi |
| m1.xlarge | 4 | 32Gi |
| n1.2xlarge | 16 | 32Gi |
| n1.4xlarge | 32 | 64Gi |
| n1.8xlarge | 64 | 128Gi |
| n1.large | 4 | 8Gi |
| n1.medium | 4 | 4Gi |
| n1.xlarge | 8 | 16Gi |
| o1.2xlarge | 8 | 32Gi |
| o1.4xlarge | 16 | 64Gi |
| o1.8xlarge | 32 | 128Gi |
| o1.large | 2 | 8Gi |
| o1.medium | 1 | 4Gi |
| o1.micro | 1 | 1Gi |
| o1.nano | 1 | 512Mi |
| o1.small | 1 | 2Gi |
| o1.xlarge | 4 | 16Gi |
| rt1.2xlarge | 8 | 32Gi |
| rt1.4xlarge | 16 | 64Gi |
| rt1.8xlarge | 32 | 128Gi |
| rt1.large | 2 | 8Gi |
| rt1.medium | 1 | 4Gi |
| rt1.micro | 1 | 1Gi |
| rt1.small | 1 | 2Gi |
| rt1.xlarge | 4 | 16Gi |
| u1.2xlarge | 8 | 32Gi |
| u1.2xmedium | 2 | 4Gi |
| u1.4xlarge | 16 | 64Gi |
| u1.8xlarge | 32 | 128Gi |
| u1.large | 2 | 8Gi |
| u1.medium | 1 | 4Gi |
| u1.micro | 1 | 1Gi |
| u1.nano | 1 | 512Mi |
| u1.small | 1 | 2Gi |
| u1.xlarge | 4 | 16Gi |
The following preference resources (cluster-wide and namespaced) are provided by this project:
| Name | Guest OS |
|---|---|
| alpine | Alpine |
| centos.stream10 | CentOS Stream 10 |
| centos.stream10.desktop | CentOS Stream 10 |
| centos.stream9 | CentOS Stream 9 |
| centos.stream9.desktop | CentOS Stream 9 |
| centos.stream9.dpdk | CentOS Stream 9 |
| cirros | Cirros |
| fedora | Fedora (amd64) |
| fedora.arm64 | Fedora (arm64) |
| opensuse.leap | OpenSUSE Leap |
| opensuse.tumbleweed | OpenSUSE Tumbleweed |
| rhel.10 | Red Hat Enterprise Linux 10 Beta (amd64) |
| rhel.10.arm64 | Red Hat Enterprise Linux 10 Beta (arm64) |
| rhel.7 | Red Hat Enterprise Linux 7 |
| rhel.7.desktop | Red Hat Enterprise Linux 7 |
| rhel.8 | Red Hat Enterprise Linux 8 |
| rhel.8.desktop | Red Hat Enterprise Linux 8 |
| rhel.8.dpdk | Red Hat Enterprise Linux 8 |
| rhel.9 | Red Hat Enterprise Linux 9 (amd64) |
| rhel.9.arm64 | Red Hat Enterprise Linux 9 (arm64) |
| rhel.9.desktop | Red Hat Enterprise Linux 9 Desktop (amd64) |
| rhel.9.dpdk | Red Hat Enterprise Linux 9 DPDK (amd64) |
| rhel.9.realtime | Red Hat Enterprise Linux 9 Realtime (amd64) |
| sles | SUSE Linux Enterprise Server |
| ubuntu | Ubuntu |
| windows.10 | Microsoft Windows 10 |
| windows.10.virtio | Microsoft Windows 10 (virtio) |
| windows.11 | Microsoft Windows 11 |
| windows.11.virtio | Microsoft Windows 11 (virtio) |
| windows.2k16 | Microsoft Windows Server 2016 |
| windows.2k16.virtio | Microsoft Windows Server 2016 (virtio) |
| windows.2k19 | Microsoft Windows Server 2019 |
| windows.2k19.virtio | Microsoft Windows Server 2019 (virtio) |
| windows.2k22 | Microsoft Windows Server 2022 |
| windows.2k22.virtio | Microsoft Windows Server 2022 (virtio) |
| windows.2k25 | Microsoft Windows Server 2025 |
| windows.2k25.virtio | Microsoft Windows Server 2025 (virtio) |