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# Apache YuniKorn - A Universal Scheduler

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Apache YuniKorn is a light-weight, universal resource scheduler for container orchestrator systems.
It is created to achieve fine-grained resource sharing for various workloads efficiently on a large scale, multi-tenant,
and cloud-native environment. YuniKorn brings a unified, cross-platform, scheduling experience for mixed workloads that consist
of stateless batch workloads and stateful services. 

YuniKorn now supports K8s and can be deployed as a custom K8s scheduler. YuniKorn's architecture design also allows adding different
shim layer and adopt to different ResourceManager implementation including Apache Hadoop YARN, or any other systems.

## Get Started

See how to get started with running YuniKorn on Kubernetes, please read the documentation on [yunikorn.apache.org](http://yunikorn.apache.org/docs/).

Want to know more about the value of the YuniKorn project, and what YuniKorn can do? Here are some
[session recordings and demos](https://yunikorn.apache.org/community/events#past-conference--meetup-recordings).

## Get Involved

Please read [get involved](http://yunikorn.apache.org/community/get_involved) document if you want to discuss issues,
contribute your ideas, explore use cases, or participate the development.

If you want to contribute code to this repo, please read the [developer doc](http://yunikorn.apache.org/docs/next/developer_guide/build).
All the design docs are available [here](http://yunikorn.apache.org/docs/next/design/architecture).

## Code Structure

Apache YuniKorn project has the following git repositories:

- [yunikorn-core](https://github.com/apache/yunikorn-core/) : the scheduler brain :round_pushpin: 
- [yunikorn-k8shim](https://github.com/apache/yunikorn-k8shim) : the adaptor to Kubernetes
- [yunikorn-scheduler-interface](https://github.com/apache/yunikorn-scheduler-interface) : the common scheduling interface
- [yunikorn-web](https://github.com/apache/yunikorn-web) : the web UI
- [yunikorn-release](https://github.com/apache/yunikorn-release/): the repo manages yunikorn releases, including the helm charts
- [yunikorn-site](https://github.com/apache/yunikorn-site/): the source code for [yunikorn website](http://yunikorn.apache.org/)

The `yunikorn-core` is the brain of the scheduler, which makes placement decisions (allocate container X on node Y) according
to the builtin rich scheduling policies. Scheduler core implementation is agnostic to the underneath resource manager system.