Feature Classification

This document presents a matrix that describes which features are ready to be used and which features are works in progress. It includes links to relevant documentation and functional tests.

Warning

Please note: this is a work in progress!

Aims

Users want reliable, long-term solutions for their use cases. The feature classification matrix identifies which features are complete and ready to use, and which should be used with caution.

The matrix also benefits developers by providing a list of features that require further work to be considered complete.

Below is a matrix for a selection of important verticals:

For more details on the concepts in each matrix, please see Notes on Concepts.

General Purpose Cloud Features

This is a summary of the key features dev/test clouds, and other similar general purpose clouds need, and it describes their current state.

Below there are sections on NFV and HPC specific features. These look at specific features and scenarios that are important to those more specific sets of use cases.

Summary

Feature Maturity Hyper-V CI Ironic CI libvirt+kvm (gate) libvirt+xen VMware CI XenServer CI
Create Server and Delete Server complete ?
Snapshot Server complete ? ? ?
Server power ops complete ?
Rebuild Server complete ?
Resize Server complete ?
Volume Operations complete
Custom disk configurations on boot complete n
Custom neutron configurations on boot complete
Pause a Server complete
Suspend a Server complete
Server console output complete
Server Rescue complete
Server Config Drive complete
Server Change Password experimental
Server Shelve and Unshelve complete

Details

NFV Cloud Features

Network Function Virtualization (NFV) is about virtualizing network node functions into building blocks that may connect, or chain together to create a particular service. It is common for this workloads needing bare metal like performance, i.e. low latency and close to line speed performance.

Summary

Feature Maturity libvirt+kvm libvirt+xen
NUMA Placement experimental m

Details

HPC Cloud Features

High Performance Compute (HPC) cloud have some specific needs that are covered in this set of features.

Summary

Feature Maturity Hyper-V CI libvirt+kvm (gate) libvirt+xen VMware CI XenServer CI
GPU Passthrough experimental l k

Details

Notes on Concepts

This document uses the following terminology.

Users

These are the users we talk about in this document:

application deployer
creates and deletes servers, directly or indirectly using an API
application developer
creates images and apps that run on the cloud
cloud operator
administers the cloud
self service administrator
runs and uses the cloud

Note

This is not an exhaustive list of personas, but rather an indicative set of users.

Feature Group

To reduce the size of the matrix, we organize the features into groups. Each group maps to a set of user stories that can be validated by a set of scenarios and tests. Typically, this means a set of tempest tests.

This list focuses on API concepts like attach and detach volumes, rather than deployment specific concepts like attach an iSCSI volume to a KVM based VM.

Deployment

A deployment maps to a specific test environment. We provide a full description of the environment, so it is possible to reproduce the reported test results for each of the Feature Groups.

This description includes all aspects of the deployment, for example the hypervisor, number of nova-compute services, storage, network driver, and types of images being tested.

Feature Group Maturity

The Feature Group Maturity rating is specific to the API concepts, rather than specific to a particular deployment. That detail is covered in the deployment rating for each feature group.

Note

Although having some similarities, this list is not directly related to the DefCore effort.

Feature Group ratings:

Incomplete
Incomplete features are those that do not have enough functionality to satisfy real world use cases.
Experimental
Experimental features should be used with extreme caution. They are likely to have little or no upstream testing, and are therefore likely to contain bugs.
Complete

For a feature to be considered complete, it must have:

  • complete API docs (concept and REST call definition)
  • complete Administrator docs
  • tempest tests that define if the feature works correctly
  • sufficient functionality and reliability to be useful in real world scenarios
  • a reasonable expectation that the feature will be supported long-term
Complete and Required

There are various reasons why a complete feature may be required, but generally it is when all drivers support that feature. New drivers need to prove they support all required features before they are allowed in upstream Nova.

Required features are those that any new technology must support before being allowed into tree. The larger the list, the more features are available on all Nova based clouds.

Deprecated

Deprecated features are those that are scheduled to be removed in a future major release of Nova. If a feature is marked as complete, it should never be deprecated.

If a feature is incomplete or experimental for several releases, it runs the risk of being deprecated and later removed from the code base.

Deployment Rating for a Feature Group

The deployment rating refers to the state of the tests for each Feature Group on a particular deployment.

Deployment ratings:

Unknown
No data is available.
Not Implemented
No tests exist.
Implemented
Self declared that the tempest tests pass.
Regularly Tested
Tested by third party CI.
Checked
Tested as part of the check or gate queue.

The eventual goal is to automate this list from a third party CI reporting system, but currently we document manual inspections in an ini file. Ideally, we will review the list at every milestone.