Virtual Machine Resources

Each virtual machine has these two configuration settings:

• instanceType defines the resourced provided to the Virtual Machine.
• instanceProfile defines the set of preferences for Virtual Machines, according to the OS being used.

Instance Type Resources

Reference table

The following instancetype resources are provided by Cozystack:

U Series

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.

O Series

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.

CX Series

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.

M Series

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.

RT Series

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.

Instance Profile Resources

The following preference resources are provided by Cozystack:

Developing Instance Types and Profiles

To get started with customizing or creating your own instancetypes and preferences see the development guide.