[YUNIKORN-2212] Outstanding request collection optimisation (#745)

Auto scaling n K8s relies on the pod to be marked unschedulable. That is
done via a regular callback from the core to the shim. The logic for
building the pod list in this callback is simple. This could cause over
scaling nodes or excessive K8s API server calls.

Improvements added:
* Don't collect requests that have not been scheduled yet.
* If already triggered scale up do not sent again
* Check for gang placeholders for any real ask
* Don't scale if pod has required node set (daemon set pod)

Track the state of scheduling and auto scale triggering.

Closes: #745

Signed-off-by: Wilfred Spiegelenburg <wilfreds@apache.org>
9 files changed
tree: 4f21b9e3e02b505f14f4c16789c43c0ff68bb143
  1. .github/
  2. cmd/
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  4. pkg/
  5. scripts/
  6. .asf.yaml
  7. .gitignore
  8. .go_version
  9. .golangci.yml
  10. go.mod
  11. go.sum
  12. LICENSE
  13. Makefile
  14. NOTICE
  15. README.md
README.md

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.

Want to know more about the value of the YuniKorn project, and what YuniKorn can do? Here are some session recordings and demos.

Get Involved

Please read 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. All the design docs are available here.

Code Structure

Apache YuniKorn project has the following git repositories:

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.