8.4 KiB
Node feature discovery for Kubernetes
- Overview
- Command line interface
- Feature discovery
- Getting started
- Building from source
- Targeting nodes with specific features
- References
- License
- Demo
NOTE: We are gathering evidence in order to graduate from the Kubernetes incubator. If you are a user of the project, please add yourself to this list with as much detail as you are comfortable providing (name and email optional).
Overview
This software enables node feature discovery for Kubernetes. It detects hardware features available on each node in a Kubernetes cluster, and advertises those features using node labels.
This project uses GitHub milestones for release planning.
Command line interface
node-feature-discovery.
Usage:
node-feature-discovery [--no-publish --sources=<sources> --label-whitelist=<pattern>]
node-feature-discovery -h | --help
node-feature-discovery --version
Options:
-h --help Show this screen.
--version Output version and exit.
--sources=<sources> Comma separated list of feature sources.
[Default: cpuid,rdt,pstate]
--no-publish Do not publish discovered features to the
cluster-local Kubernetes API server.
--label-whitelist=<pattern> Regular expression to filter label names to
publish to the Kubernetes API server. [Default: ]
Feature discovery
Feature sources
The current set of feature sources are the following:
- CPUID for x86 CPU details
- Intel Resource Director Technology
- Intel P-State driver
Feature labels
The published node labels encode a few pieces of information:
- A "namespace" (e.g.
node.alpha.kubernetes-incubator.io/nfd). - The version of this discovery code that wrote the label, according to
git describe --tags --dirty --always. - The source for each label (e.g.
cpuid). - The name of the discovered feature as it appears in the underlying
source, (e.g.
AESNIfrom cpuid).
Note: only features that are available on a given node are labeled, so
the only label value published for features is the string "true".
{
"node.alpha.kubernetes-incubator.io/node-feature-discovery.version": "v0.1.0",
"node.alpha.kubernetes-incubator.io/nfd-cpuid-<feature-name>": "true",
"node.alpha.kubernetes-incubator.io/nfd-rdt-<feature-name>": "true",
"node.alpha.kubernetes-incubator.io/nfd-pstate-<feature-name>": "true"
}
The --sources flag controls which sources to use for discovery.
Note: Consecutive runs of node-feature-discovery will update the labels on a given node. If features are not discovered on a consecutive run, the corresponding label will be removed. This includes any restrictions placed on the consecutive run, such as restricting discovered features with the --label-whitelist option.
Intel Resource Director Technology (RDT) Features
| Feature name | Description |
|---|---|
| RDTMON | Intel Cache Monitoring Technology (CMT) and Intel Memory Bandwidth Monitoring (MBM) |
| RDTL3CA | Intel L3 Cache Allocation Technology |
| RDTL2CA | Intel L2 Cache Allocation Technology |
CPUID Features (Partial List)
| Feature name | Description |
|---|---|
| ADX | Multi-Precision Add-Carry Instruction Extensions (ADX) |
| AESNI | Advanced Encryption Standard (AES) New Instructions (AES-NI) |
| AVX | Advanced Vector Extensions (AVX) |
| AVX2 | Advanced Vector Extensions 2 (AVX2) |
| BMI1 | Bit Manipulation Instruction Set 1 (BMI) |
| BMI2 | Bit Manipulation Instruction Set 2 (BMI2) |
| SSE4.1 | Streaming SIMD Extensions 4.1 (SSE4.1) |
| SSE4.2 | Streaming SIMD Extensions 4.2 (SSE4.2) |
| SGX | Software Guard Extensions (SGX) |
Getting started
System requirements
- Linux (x86_64)
- [kubectl] kubectl-setup (properly set up and configured to work with your Kubernetes cluster)
- [Docker] docker-down (only required to build and push docker images)
Usage
Feature discovery is done as a one-shot job. There is an example script in this repo that demonstrates how to deploy the job to unlabeled nodes.
./label-nodes.sh
The discovery script will launch a job on each each unlabeled node in the
cluster. When the job runs, it contacts the Kubernetes API server to add labels
to the node to advertise hardware features (initially, from cpuid, RDT and p-state).
Building from source
Download the source code.
git clone https://github.com/kubernetes-incubator/node-feature-discovery
Build the Docker image:
cd <project-root>
make
NOTE: Our default docker image is hosted in quay.io. To override the
QUAY_REGISTRY_USER use the -e option as follows:
QUAY_REGISTRY_USER=<my-username> make docker -e
Push the Docker Image (optional)
docker push <quay-domain-name>/<registry-user>/<image-name>:<version>
Change the job spec to use your custom image (optional):
To use your published image from the step above instead of the
quay.io/kubernetes_incubator/node-feature-discovery image, edit line 40 in the file
node-feature-discovery-job.json.template
to the new location (<quay-domain-name>/<registry-user>/<image-name>[:<version>]).
Targeting Nodes with Specific Features
Nodes with specific features can be targeted using the nodeSelector field. The
following example shows how to target nodes with Intel TurboBoost enabled.
{
"apiVersion": "v1",
"kind": "Pod",
"metadata": {
"labels": {
"env": "test"
},
"name": "golang-test"
},
"spec": {
"containers": [
{
"image": "golang",
"name": "go1",
}
],
"nodeSelector": {
"node.alpha.kubernetes-incubator.io/nfd-pstate-turbo": "true"
}
}
}
For more details on targeting nodes, see node selection.
References
Github issues
Kubernetes Incubator
This is a Kubernetes Incubator project. The project was established 2016-08-29. The incubator team for the project is:
- Sponsor: Dawn Chen (@dchen1107)
- Champion: David Oppenheimer (@davidopp)
- SIG: sig-node
License
This is open source software released under the Apache 2.0 License.
Demo
A demo on the benefits of using node feature discovery can be found in demo.