KWOK (Kubernetes WithOut Kubelet) #

KWOK is pronounced as /kwɔk/.

KWOK is a toolkit that enables setting up a cluster of thousands of Nodes in seconds. Under the scene, all Nodes are simulated to behave like real ones, so the overall approach employs a pretty low resource footprint that you can easily play around on your laptop.

What is KWOK? #

KWOK stands for Kubernetes WithOut Kubelet. So far, it provides two tools:

• kwok is the cornerstone of this project, responsible for simulating the lifecycle of fake nodes, pods, and other Kubernetes API resources.
• kwokctl is a CLI tool designed to streamline the creation and management of clusters, with nodes simulated by kwok.

What’s the difference with kubemark #

kubemark is a kubelet that does not actually run a container. Its behavior is exactly the same as kubelet, which means that simulating a large number of nodes and pods requires a lot of memory.

kwok, however, simply simulates the behavior of the node. As a result, it can simulate a large number of nodes and pods using very little memory.

What’s the difference with kind #

kind runs Kubernetes in Docker, creating a real cluster.

kwokctl can be used as an alternative to kind in some scenarios where you don’t need to actually run any pod.

Why KWOK? #

• Lightweight: You can simulate thousands of nodes on your laptop without significant consumption of CPU or memory resources. Currently, KWOK can reliably maintain 1k nodes and 100k pods easily.
• Fast: You can create and delete clusters and nodes almost instantly, without waiting for boot or provisioning. Currently, KWOK can create 20 nodes or pods per second.
• Compatibility: KWOK works with any tools or clients that are compliant with Kubernetes APIs, such as kubectl, helm, kui, etc.
• Portability: KWOK has no specific hardware or software requirements. You can run it using pre-built images, once Docker/Podman/Nerdctl is installed. Alternatively, binaries are also available for all platforms and can be easily installed.
• Flexibility: You can configure different node types, labels, taints, capacities, conditions, etc., and you can configure different pod behaviors, status, etc. to test different scenarios and edge cases.

Getting Started #

The animation below shows a test process to work with the latest version of kwok/kwokctl.

Welcome to get started with the installation, basic usage, custom configuration, and contribution to KWOK.

kwokctl Runtime Support Matrix #

Runtime indicates which medium kwokctl will use to start the cluster

• 🟢 Supported and test covered by CI
• 🔵 Supported and test by manually
• 🟣 Supported but not test yet (need help to verify)
• 🟤 Unsupported but should work in theory (need help to verify)
• 🔴 Unsupported and will not work
• 🟠 Need to build platform-specific Kubernetes binaries
• 🟡 Need to do some workaround to make it work

Community #

See our own contributor guide and the Kubernetes community page.

Getting Involved #

If you’re interested in participating in future discussions or development related to KWOK, there are several ways to get involved:

• Slack: #kwok for general usage discussion, #kwok-dev for development discussion. (visit slack.k8s.io for a workspace invitation)
• Open Issues/PRs/Discussions in sigs.k8s.io/kwok

Code of conduct #

Participation in the Kubernetes community is governed by the Kubernetes Code of Conduct.