YuniKorn Concepts

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Revision as of 21:06, 13 December 2023 by Ovidiu (talk | contribs) (→‎Node)
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Internal

Plugin Mode

Resource Manager (RM)

YuniKorn communicates with various implementation of resource management systems (Kubernetes, YARN) via a standard interface defined in the yunikorn-scheduler-interface package.

Allocation

A core scheduler-level concept. An allocation can be in one of two states ("Pending" and "In-Progress"). A pending allocation is one which has been decided upon by YuniKorn but has not yet been communicated to the default scheduler via PreFilter()/Filter(). Once PreFilter()/Filter() pass, the allocation transitions to "In-Progress" to signify that the default scheduler is responsible for fulfilling the allocation. Once PostBind() is called in the plugin to signify completion of the allocation, it is removed.

Application

Application Metadata

Application ID

Looks in this order:

  • Annotation "yunikorn.apache.org/app-id"
  • Label "applicationId"
  • ...

Queue Name

User

Tags

Groups

TaskGroups

OwnerReference

Usually a pod, designated by its UID.

Scheduling Policy Parameters

Application Task

For the Kubernetes implementations, Kubernetes pods are mapped onto YuniKorn Core Tasks, and the task ID is the pod UID.

A task may be the "originator" of the Application, if it's the first one seen for the application. If that is the case, it is considered "first pod"/"owner"/"driver".

Task Metadata

Application ID

TaskID

(same as the Pod ID)

Pod

Placeholder

TaskGroupName

Task Group

Node

Can a node be declared to be part of a partition with the "si/node-partition" label? It seems that the node Attributes partially come from the node labels.

Partition

The total "partition resource" is the sum of its nodes' "capacity" (node.GetCapacity(), which is the node's "total resource").

Configuration

Context

yunikorn-k8shim cache.Context

Resource

Quantity

Queue

A namespace can have a "queue" if annotated with "yunikorn.apache.org/queue".

A namespace can have a "parent queue" is annotated with "yunikorn.apache.org/parentqueue".